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Are Computers Ready to Create Mathematical Proofs?

DoraLives writes "Interesting article in the New York Times regarding the quandary mathematicians are now finding themselves in. In a lovely irony reminiscent of the torture, in days of yore, that students were put through when it came to using, or not using, newfangled calculators in class, the Big Guys are now wrestling with a very similar issue regarding computers: 'Can we trust the darned things?' 'Can we know what we know?' Fascinating stuff."

441 comments

  1. Rumsfeld, anyone? by dolo666 · · Score: 5, Funny

    > 'Can we know what we know?' Fascinating stuff.

    Reminds me of Rumsfeld... "Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know."

    1. Re:Rumsfeld, anyone? by jpBabelFish · · Score: 0

      As we have known, because there is knowns which is known, something always is interesting in me, a report that it did not happen,; As for us there are times when we have known that you have known. In addition as for us you know that it is the unknown which is known; Namely we have known that it is a certain thing which we do not know. But and -- where it has unknown unknown as for us those where we do not know that you do not know.

    2. Re:Rumsfeld, anyone? by kfg · · Score: 2, Funny

      Are you sure?

      KFG

    3. Re:Rumsfeld, anyone? by sisco · · Score: 1

      "Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know."

      What about 'unknown knowns?' That is to say, the things we should know, but we forgot somewhere along the way?

      --
      DATA comments; PROC SORT DATA = comments BY score; PROC DELETE comments >> 1; RUN; DATA entertainment SET commen
    4. Re:Rumsfeld, anyone? by Tower · · Score: 5, Informative

      Actually, this is three of the four quadrants of knowledge...

      KK | KD
      ___|____
      |
      DK | DD

      So, you can:
      Know that you Know something
      Know that you Don't Know something (the second most common)
      Don't Know that you Don't Know something (most things fall in this category for most people)
      Don't Know that you Know something (the most interesting of the categories)

      Big, huge, red tape operations can easily fall into the latter category (DK)... since it is rather easy for a group to obtain knowledge, yet be unaware of it [political commentary omitted].

      --
      "It's tough to be bilingual when you get hit in the head."
    5. Re:Rumsfeld, anyone? by Deraj+DeZine · · Score: 4, Funny

      Well, I had been in the don't care that I don't know category; now I'm in the don't care that I know. Great.

      --
      True story.
    6. Re:Rumsfeld, anyone? by cs · · Score: 5, Interesting

      Can't remember where I came across this, but for entertainment:

      Men are four:
      He who knows and knows that he knows; he is wise, follow him.
      He who knows and knows not that he knows; he is asleep, wake him.
      He who knows not and knows that he knows not; he is ignorant, teach him.
      He who knows not and knows not that he knows not; he is a fool, spurn him!

      I'm sure it's coloured my attitude to supporting users:-)

      --
      Cameron Simpson, DoD#743 cs@cskk.id.au http://www.cskk.ezoshosting.com/cs/
    7. Re:Rumsfeld, anyone? by jgabby · · Score: 5, Funny

      Then there's:

      My boss, who knows that he knows not;
      But pretends that he knows that he knows;
      And he's so convincing at it, that;
      People who know that he doesn't know;
      Beleive that he knows that he knows anyway.

    8. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      How is this Informative? This should be be moderated down to +1 Obvious.

    9. Re:Rumsfeld, anyone? by aducore · · Score: 1

      Really, shouldn't there be 2^n classifications of knowledge, since you could know that you know that you know, or not know that you know that you know, etc.? Where n is taken to be some measure of confidence.

      Really, though, unless n is infinite, it's hard to make definite claims on anything since we don't know that we know the first link in the chain, and all proofs are based on assumptions, so we can't prove anything to be definite. So, how can we know anything? I think we should use the word think instead of know.

      cognitive science is a bottomless pit, if you ask me.

    10. Re:Rumsfeld, anyone? by sbaker · · Score: 4, Interesting

      I'm not sure that there are only those four catagories.

      Godels theorem pretty much says that there are things that you can NEVER know are true or false...and that in some cases you can PROVE that you can never know them.

      This leads to some other states that your knowledge can be in:

      CERTAINTY OF UNCERTAINTY: In some cases you can know (by solid mathematical proof) that you can never know some particular thing. For example. we know with absolute certainty - that you can't solve the 'Halting Problem' (to prove whether an arbitary computer program will eventually halt or whether it'll run forever). That's something we KNOW we'll never be able to do no matter how smart we get. That's not the same as KK/KD/DK or DD. It's tempting to lump this in with KD - but in the case of simply being aware that we are ignorant of something, we might take steps to resolve that ignorance. In this case, we know that this is something we cannot EVER know.

      CERTAINTY OF POTENTIAL CERTAINTY: If you know the current "largest prime number" - then by definition, you don't know of a larger prime - but you DO know that you could definitely find a larger prime if you really wanted to.

      UNCERTAINTY OF POTENTIAL CERTAINTY: Then there are other things that you might not know whether they are knowable or not - such as the proof of some of the classic mathematical problems. Before Fermat's last theorem was proved, nobody was sure whether it could be proved or not.

      --
      www.sjbaker.org
    11. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      spurn. my new word for the day

    12. Re:Rumsfeld, anyone? by benna · · Score: 2, Insightful

      There was a young man who said, "though
      it seems that I know that I know,
      what I would like to see
      is the I that sees me,
      when I know that I know that I know."

      Great poem, Alan Watts used to quote it alot when talking about the illusion of the ego.

      --
      "It is not how things are in the world that is mystical, but that it exists." -Ludwig Wittgenstein
    13. Re:Rumsfeld, anyone? by Photar · · Score: 1

      Seems familiar.

      --
      He who knows not and knows he knows not is a wise man. He who knows not and knows not he knows not is a fool.
    14. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      Or to put it more concisely, "It's not what you don't know that kills you,... it's what you know that isn't so."

      Memo to Bush: Campaign motto for 2004: "It's the unknown unknowns, stupid!"

    15. Re:Rumsfeld, anyone? by unknown51a · · Score: 0

      Reminds of a speech John Prescott made once...
      "There are known knowns, unknown knowns, known unknowns, unknown unknowns..." and then he swore asked if he could do that again

      --
      I had an imaginary sig once, he said I was a loser and ran off.
    16. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      Most things fall into the category "don't know that you don't know" for ALL people.

    17. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      You really didn't get any of this did you?

      CERTAINTY OF UNCERTAINTY - wether you take steps to resolve ignorance, wether you can, and wether you know you can or can't has absolutely nothing to do with the knowledge an sich. You are simply lumping a few different pieces of knowledge together and then proclaim them to be one, nonsense. The Halting Problem itself is 100% KD, you even say it yourself, we know that we don't know the answer (if a certain algorithm will run forever or not). The fact that it is mathematically unprovable is a completely different piece of knowledge, a KK one to be precise, we Know that we Know it's unprovable.

      CERTAINTY OF POTENTIAL CERTAINTY - More lumping together of different pieces of knowledge. Knowing a larger prime number then P is completely different from knowing that we are capable of finding a larger prime number then P. The first piece of knowledge is nothing more then a string of numbers. The second is a mathematical proof that for each prime number P, there is another prime number Q whereby Q > P.

      UNCERTAINTY OF POTENTIAL CERTAINTY - repeated the mistake again. Fermat's theorem itself and the fact wether it could be proven to be right or not are two different things.

      Any other DD problems I can solve for you?

    18. Re:Rumsfeld, anyone? by jeremyp · · Score: 1

      Godel's theorem says that any formalised version of number theory is either incomplete or inconsistent. i.e. either there are true statements that cannot be proved within the system or there are statements where both they and there negations can be proved within the system.

      You cannot prove that a statement is undecidable in any general sense only that it is undecidable within some system e.g. a Turing Machine or Russell and Whitehead's Principia Mathematica. A moment's thought is enough to confirm this: If I have proved that theorem T is undecidable, it follows that there must be no counter example to theorem T, because a counter example would constitute a proof of the negation of T which means that T is decidable. If there are no counter examples, T must be true, so T is decided.

      --
      All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
    19. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      Reminds me of Godel.
      There are things that are true, but not proofable.

    20. Re:Rumsfeld, anyone? by PhotoGuy · · Score: 1

      Know that you Know something
      Know that you Don't Know something (the second most common)
      Don't Know that you Don't Know something (most things fall in this category for most people)
      Don't Know that you Know something (the most interesting of the categories)

      These are also known as:

      Unconscious incompetence
      Conscious incompetence
      Conscious competence
      Unconscious competence

      Generally people go through learning something new in that order, too. I remember vividly seeing this when i learned to sail. I didn't even know I couldn't do it worth a damn (unconscious incompetence); I then realized I couldn't do it (conscious incompetence); as I got better at it, I was getting good at it, but had to think about it while I was doing it (conscious competence); finally, it became second nature, and I didn't have to think about most aspects of it (unconscious competence).

      Most people have gone through the same stages when learning to drive; 1) doesn't look so hard; 2) man, those brakes are sensitive, how the hell do I work the clutch; 3) hey, I can do this, I'm getting the hang of it; 4) blah, blah, blah on the cell phone while applying makeup and drinking a milkshake.

      --
      Love many, trust a few, do harm to none.
    21. Re:Rumsfeld, anyone? by mrogers · · Score: 1

      So are there formal versions of number theory in which Godel's theorem can't be proved?

    22. Re:Rumsfeld, anyone? by mrogers · · Score: 1
      Self-knowledge seems like a paradox, but consider that it takes some amount of time, no matter how small, to experience a sensation - even the sensation of knowing something about yourself. So the "self" that you know something about is a version of yourself from the recent past... and the "self" that he or she knows something about is a version from the slightly more distant past. Instead of an apparently paradoxical circle you have a spiral in time. You can follow it back as far as you like, with each version's self-knowledge getting less and less acute until the ego disappears altogether in infancy.

      So you can see "the I that sees me" - you just have to wait a second. ;-)

    23. Re:Rumsfeld, anyone? by Anonymous Coward · · Score: 0

      That leaves out too much of Rumsfled's knowledge: the things he thinks he knows, but he doesn't truly know. Why does Bush listen to this toady?

    24. Re:Rumsfeld, anyone? by cheekyboy · · Score: 1

      and i thought you were talking about Rumsfield talking about iraqs WMD.

      --
      Liberty freedom are no1, not dicks in suits.
    25. Re:Rumsfeld, anyone? by dustman · · Score: 1

      Godels theorem pretty much says that there are things that you can NEVER know are true or false...

      One thing I have always wondered about Godel's theorem, maybe someone here can answer it...

      Consider integers. All integers are either positive or negative, with one exception, zero. (It might be that zero is defined to be one or the other, I don't know, but it's not important to this question).

      My question:
      Godel's theorem proves that there are some true statements which can't be proven. But, is there any answer in math as to whether or not only pathological Godel statements fall into this category?

    26. Re:Rumsfeld, anyone? by elhaf · · Score: 1

      Goedel's theorem is equivalent to the Halting Problem in computability. Certainly we as programmers would like to know if our programs halt before we run them, so our compiler should tell us this. But it cannot. Likewise, we'd like to know if a grammar is ambiguous. We cannot determine this automatically, for the same reason. In fact, we'd like to know if a particular program computes a particular function. But Rice's theorem follows from all this and tells us we cannot automatically determine this in general. To me, these seem like practical, not pathological, problems.

      --
      Six score characters.
      Brevity being wit's soul
      I have enough space.
    27. Re:Rumsfeld, anyone? by benna · · Score: 1

      With all that its much easier just to drop the idea of an ego entirly. Everything you do is the result of someone else in the universe. At the same time you are part of that universe so you affect everything else. There is then no longer a need for an ego to make decisions, its an illusion. This is not a deterministic idea because nothing is happening to anyone. But at the same time nobody is DOING anything. Its all just a happening.

      --
      "It is not how things are in the world that is mystical, but that it exists." -Ludwig Wittgenstein
    28. Re:Rumsfeld, anyone? by Skiboricus · · Score: 1

      I wish I had MOD points to give for that. Brilliant!

    29. Re:Rumsfeld, anyone? by mrogers · · Score: 1
      True, but even so if you believe you're making decisions it "all just happens" differently than if you believe it all just happens.

      Personally I can't help believing in free will, but if you want to be a fatalist that's your choice. ;-)

    30. Re:Rumsfeld, anyone? by anotherone · · Score: 1

      Possibly things we know that we don't even realise that we know- think Gravity, pre-newton.

      --
      Username taken, please choose another one.
    31. Re:Rumsfeld, anyone? by benna · · Score: 1

      There is however some distinction between what I said and fatalism. Fatalism is the view that we are powerless to do anything other that what we actually do. I am arguing "we" actually "do" nothing because there is no "we" or ego to do it. For someone to do anyting the ego must exist.

      --
      "It is not how things are in the world that is mystical, but that it exists." -Ludwig Wittgenstein
    32. Re:Rumsfeld, anyone? by jwise · · Score: 1

      It depends what you mean by pathological statements. There are certainly interesting statements that are undecidable, for example the continuum hypothesis (the cardinality of the set of real numbers is equal to the cardinality of the first uncountable ordinal) is undecidable given the axioms of set theory.

      However, I think what you are asking is if every undecidable statement that is true can be given by some kind of Godel construction. I think the answer to this is no. A proof might go like this:

      Define an axiom A which says: any statement which is a Godel construction is true. Adjoin this to your list of axioms. Then Godel's incompleteness theorem says that there will be an undecidable statement in this extended system of axioms.

      Jonathan

  2. Can someone elaborate on... by Anonymous Coward · · Score: 2, Interesting

    ...precisely why it's so hard to see that a pyramid of cannonballs is an optimal stack? This seems almost axiomatic.

    I guess the obvious Monte Carlo simulation doesn't constitute "proof," but still, what exactly is the big question here?

    1. Re:Can someone elaborate on... by stephentyrone · · Score: 5, Informative

      It's not hard to *see*. It's hard to *prove*. Very little of mathematics is consumed with proving deep, mystical statements that no one would ever anticipate to be true. Much (maybe most) of mathematics is built around proving (relatively) obvious things. Why bother? because sometimes, relatively obvious things turn out to be false, and there's no way to know that they won't until you've prooved them true. In general, showing that discrete (or semi-discrete) phenomena are optimal is fairly tricky; you can't just appeal to calculus to optimize some function. You often have to somehow break the search space up into a bunch of disjunct cases that span all the possibilities, and be able to prove that they span all possibilities. Then, if you're lucky, you can use some kind of calculus-type argument on the continuous spaces you're left with.

    2. Re:Can someone elaborate on... by baywulf · · Score: 2, Insightful

      Sometimes a precise mathematical analysis can lead to startling insights. Perhaps there are multiple solutions equally optimal. Perhaps it gives a general algorithm that works for other shapes.

    3. Re:Can someone elaborate on... by Guppy06 · · Score: 1

      Most people just get hung up on the term "brass monkey" and snicker.

    4. Re:Can someone elaborate on... by uncleO · · Score: 3, Informative

      What if the stack is very large, for instance? Is it still obvious that the pyramid is best? Consider a similar problem, that of packing squares in a rectangle. When the rectangle is small, it is obvious that the best way is to pack them together starting from one corner, leaving a little wastage on the opposite two sides. It seems strange, but it is true, that when the recangle is very large, this strategy is not optimal. More squares can be packed when they are not packed in such a regular pattern. This is the main difficulty with proofs of this type. It can be easy to prove that a given strategy is not optimal, but not so simple to show that no better strategy can exist.

    5. Re:Can someone elaborate on... by JoranE · · Score: 2, Interesting

      Definition of optimal: At least as good as EVERY other possible configuration of (in this case infinitely many) oranges in 3-space.

      If by "see" you mean "conjecture" then, yes, it is easy to see. If by "see" you mean "prove", and thereby catch a glimpse into the fundemental reasons WHY this is the best possible stacking, then it is exceedingly difficult.

      How would you go about designing a proof that would take into account every single one of the infinitely many configurations of oranges? Could you even list them? Indeed, I read somewhere that Hales said that the hardest part was reducing all the infinitely many configurations into something like 5,000 cases.

      Focus on the infinite part of this problem: we're looking for an arrangement of infinitely many oranges in space such that we maximize the density of the oranges. Now, is it obvious to you that an (infinite) pyramid is denser than packing them somehow into a sphere-ish shape (with infinite radius of course)? It certainly isn't to me...

      I'm not sure is this is very convincing, but it's the best I can do without really researching the problem.

    6. Re:Can someone elaborate on... by the_2nd_coming · · Score: 1

      dude...obvious things are the hardest to prove.

      prove to me that 0 1

      that proof takes about 15 - 20 lines of crap just to prove that 0 1.

      your a physics student aren't you.

      --



      I am the Alpha and the Omega-3
    7. Re:Can someone elaborate on... by the_2nd_coming · · Score: 1

      damn HTML.

      Obvious things are hardest to prove.

      prove to me that 0 is less than 1.

      that proof takes about 15 - 20 lines of crap.

      pretty long just to prove something that is so obvious.

      your a physics person aren't you.

      --



      I am the Alpha and the Omega-3
    8. Re:Can someone elaborate on... by conan776 · · Score: 0
      Don't ask me. AKAICT a recursive algorithm would get this right away.
      Is zero oranges the most dense? Duh, then:
      while forever do {
      pack another orange.
      if (not a pyramid shaped packing) goto kepler sux;
      }
      kepler sux: you weren't sposed to be able to get here!
      OK, where's my nobel prize in mathematics??
      --
      "Reality is that which, when you stop believing in it, doesn't go away." -- Philip K. Dick
    9. Re:Can someone elaborate on... by adamruck · · Score: 2, Insightful

      um.... your wrong about that... and alot of people dont understand this either.

      all of our knowledge is based upon assumptions. For instance when it comes to the number systems... we have a set of assumtions that we say are true.. and there is no arguing about it. For instance in the binary system. We say the language only consists of 0 and 1. We say there are two operators and define there operations. AND/OR... we say 0 and 0 is 0.... we say 1 and 1 is one. There is NO PROOFING THIS... its a given. We can PROOF things like demorgans therom.

      This applies to many many areas... geometry... algebra.. calc... logic... etc. There are a list of assumptions that are given to be true. You could argue that calc is just an extention of algebra and geometry... but thats another matter.

      The question I think this article is asking ... is can we program this truths into a computer... give a program a problem... have it randomly(or not for the ai people) apply some theory.. and get an actual answer?

      In my own personal opinion, I think this would work. I think if you took it far enough.. giving information about math... chemistry and physics and electronics.... I think it would be possible to have a computer design a better computer.

      --
      Selling software wont make you money, selling a service will.
    10. Re:Can someone elaborate on... by CommieOverlord · · Score: 3, Insightful
      Because if you do that you've failed to do two things:
      1. Failed to demonstrate that the observed phenomenon is consistent across all possible sets (up to infinite size) of oranges, instead of the one set you have.
      2. Failed to demonstrate that the oberved phenomenon is consistent across every possible method of stacking.

        What you've done is shown that for a subset of the sets of oranges and a subset of the sets of stacks the pyramid is better.

        A mathematical proof shows something is true for every single element of the sets.
    11. Re:Can someone elaborate on... by Anonymous Coward · · Score: 0

      An "algorithm" is only an algorithm if you can prove that it terminates after a finite number of steps. See Hilbert's Tenth Problem.

    12. Re:Can someone elaborate on... by Keith+McClary · · Score: 1

      Same with packing circles into a rectangle.
      For small rectangles the best solution is a rectangular array.
      For larger rectangles a hexagonal array is better.

      More squares can be packed when they are not packed in such a regular pattern.

      I'll have to think about that.

    13. Re:Can someone elaborate on... by Anonymous Coward · · Score: 0

      Principal Mathematica, kthxbye~

    14. Re:Can someone elaborate on... by stephentyrone · · Score: 1

      questions of halting aside, this still wouldn't constitute a proof - there's no guarantee that the optimal way to pack 7 oranges can be acheived by adding one orange to the optimal arrangement of 6 oranges. Even if you *could* prove that, you'd have to also prove that the optimal way to pack infinitely many oranges can be acheived by adding (infintely many) oranges, one at a time, to the optimal way to arrange *every* finite number of oranges.

      so, basically this "algorithm" doesn't get you anywhere.

    15. Re:Can someone elaborate on... by ColaMan · · Score: 1

      It's rather complicated , but if it's based upon Kepler's stacking problem, it's only taken 300 years to get a proof sorted.

      Google it thusly.
      Summary by some guy :
      Professor Thomas Hales of the Massachusetts Institute of Technology announced in 1999 that he had posted on the Internet the solution to a seemingly simple problem that has taxed the brains of some of the finest mathematicians for 300 years. If the proof is accepted as complete (which now seems likely), Kepler's Stacking Problem will have been solved through a combination of human ingenuity and the power of modern computers.

      So it seems that yes, computers *are* ready to do proofs for us.

      All praise the power of modern computers!

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
    16. Re:Can someone elaborate on... by cagle_.25 · · Score: 1

      It has been previously proven that no regular arrangement is more dense that the pyramid. What was unknown was whether some irregular and complicated arrangement might be more dense. See here for more detail.

      --
      Human being (n.): A genetically human, genetically distinct, functioning organism.
    17. Re:Can someone elaborate on... by pVoid · · Score: 1
      Hhmm..

      The terms obvious and 'profound mystical' need a little defining here. I find it pretty damn mystical and profound that the sum from 0 to plus infinity of 1/x diverges. Despite the fact that it gets smaller and smaller.

      I find it just as mystical that 1/x^y where y > 1 converges.

      I find it a hell of a mystical that 1/xlnx does not converge.

      The real problem, I would have answered to the parent, is that a proof is a much more difficult thing than most people think it is: case in example, I've had to prove that 1 was greater than 0 in real analysis exams. That with only the axiom that 1 != 0, and Archimedes' principle (was it Archimedes? it was a long time ago).

      Anyways, I remember in class people being clearly disconcerted by the fact that the teacher even asked such a 'bland' question... "what do you mean prove it? It just *IS*..." some shouted.

      Well, it ain't. Proof's need to be and are airtight.

    18. Re:Can someone elaborate on... by tiled_rainbows · · Score: 1

      Oblate Sphereoids? Like skittles? So how many skittles can you get in a pint beer glass? And how much space for beer would there be left over?

      This would give us the highest possible skittle / beer ratio for skittlebrau (with the lowest possible obviously being a single skittle in the bottom of a pint of beer). Once we've defined these two extremes, trail and error will enable us to determine the optimum point (in terms of flavour etc) in the middle.

    19. Re:Can someone elaborate on... by ahem · · Score: 1
      It seems strange, but it is true, that when the rec(t)angle is very large, this strategy is not optimal. More squares can be packed when they are not packed in such a regular pattern.

      I'd like to see a proof of that...

      No, seriously. I would

      Stop laughing. I mean it

      --
      Not A Sig
    20. Re:Can someone elaborate on... by the_2nd_coming · · Score: 1

      I am not wrong... just because your Math skills do not give you the knowledge and tools to understand the proof that goes into proving that 01 does not make me wrong.

      read up Analysis of the real numbers, learn the field axioms which happens to be the tools we use to prove 0 1.

      don't tell someone who knows more than you that he is wrong.

      --



      I am the Alpha and the Omega-3
    21. Re:Can someone elaborate on... by the_2nd_coming · · Score: 1

      I am not wrong... just because your Math skills do not give you the knowledge and tools to understand the proof that goes into proving that 0 less than 1 does not make me wrong.

      read up Analysis of the real numbers, learn the field axioms which happens to be the tools we use to prove 0 less than 1.

      don't tell someone who knows more than you that he is wrong.

      --



      I am the Alpha and the Omega-3
  3. I don't care by fresh27 · · Score: 1

    I'll use a calculator as long as it's easier, screw accuracy.

    --
    http://ipod.fresh27.net/
    1. Re:I don't care by Vancorps · · Score: 3, Interesting
      That can actually be a good point, when you make a task faster and easier then you can sacrifice a little accuracy here and there.

      When the results become too inaccurate then you have to change your tools, so unless accuracy is key, such as NASA's calculations and the likes then you work on making a computer do as much as possible to eliminate human error and humans can be there to adjust the almost mythic fudge factor

    2. Re:I don't care by colmore · · Score: 1

      yes but these are proofs, not engineering calculations, there's no such thing as a margin of error when your possible answers are "yes" and "no"

      while in practice, there is a grey area, the intuition of a good mathematician can still be correct even if he or she makes a few small errors in explaining it rigorously, a formal proof should still aspire to a standard of perfect rigor.

      --
      In Capitalist America, bank robs you!
    3. Re:I don't care by Vancorps · · Score: 2, Insightful
      That is certainly true, so if a computer screws up portion in the middle and the answer still comes out correct then the end result is the same.

      Another post mentioned that computers could come up with the proofs but it would be too hard for a human to verify. At what point can be start to both trust the output and to build upon that trusted output by further trusting future output. It could be an interesting time in which we don't understand how things are done but we are able to do them none the less. It all comes down to the question, how much do you want to trust a machine?

    4. Re:I don't care by Anonymous Coward · · Score: 0

      It could be an interesting time in which we don't understand how things are done but we are able to do them none the less.

      No, its not that that we dont understand, its that we couldnt understand. People chose to not understand lots of things, cars, computers, string theory...

      But imagine getting to the point to where its not possible to understand everything the computer is spitting out, or at least have it require more than your lifetime for complete verification.

      As a race, I think we can see our limitations, if not now, then down the road. The trick is to change future generations to not have them.

    5. Re:I don't care by Vancorps · · Score: 1

      I suspect a beowolf cluster of math geeks could probably piece together the output of anything the computer would produce in the near future. The more layers of abstration the harder it will get, especially if they are using genertic algorithms which just get smarter and smarter the more they encounter.

  4. Create vs. Verify by Squeamish+Ossifrage · · Score: 5, Informative

    The headline does a slight disservice in describing the article that way: Whether or not computers can create proofs isn't an issue. The problem comes when the resulting proof is too involved to be verified by a human, and so the computer's work has to be trusted.

    1. Re:Create vs. Verify by Dr+Tall · · Score: 1

      Not knowing much about this stuff, I'm kind of confused. What good is a proof that is too complicated to be understood? Can it still be useful without understanding its basis other than HAL said?

    2. Re:Create vs. Verify by Vancorps · · Score: 4, Insightful
      If humans created the computer to do the task should they not trust that it would do the task and do it well? Perhaps, perhaps not.

      A computer could quite easier come up with a very complex answer simply because it can do more calculations in a given second than a human can. Of course humans take in a lot more variables at a given time so the numbers are actually very opposite but I'm sure you get my point.

      I think you test it with progressively more different problems, if the answers come out precise and accurate then you can build your level of trust in the system. Kind of like the process of getting users to trust saving to the server after a bad crash wiped everything because the previous admin was a moron.
    3. Re:Create vs. Verify by Ichijo · · Score: 1
      The problem comes when the resulting proof is too involved to be verified by a human, and so the computer's work has to be trusted.

      When something is too involved for a human to accomplish -- isn't this what we have computers for? So the solution is simple. Produce another system to verify the first system's proof. Ideally, this second system should be built by a group completely separate from the first so as not to inherit any design flaws or false assumptions.

      The same methodology could be applied to electronic voting. Everyone votes twice, once on each of two machines from two different manufacturers, and at the end of the day the results are tallied separately and compared.

      --
      Any sufficiently unpopular but cohesive argument is indistinguishable from trolling.
    4. Re:Create vs. Verify by NanoGator · · Score: 1

      "The problem comes when the resulting proof is too involved to be verified by a human, and so the computer's work has to be trusted."

      Just to clarify, do you mean the computer's accuracy in moving the bits around, or do you mean the human who wrote the program didn't make any mistakes?

      --
      "Derp de derp."
    5. Re:Create vs. Verify by Xilo · · Score: 4, Insightful

      involved, not complicated - like the Four Color [Conjecture]. Noone could figure out a way to actually prove it, so some one (or group of someones) wrote a program to systematically determine all the possible arrangements of regions in a simplified series of maps, and then figure out how to color each of those maps. The involved part was .. well, all of it. It wasn't necessarily very complicated, just labor-intensive. Computers are perfectly suited for tedium.

      --
      Read; Write; Execute
    6. Re:Create vs. Verify by Llywelyn · · Score: 4, Insightful

      Sometimes it is enough to know that something is *true* or *false* without having to know the details of the in-between steps.

      I'll give some trivial examples to illustrate:

      For a famous example, it would provide a great deal of peace of mind if we could prove that P != NP. It wouldn't matter that we understand that proof so much as that it is *provably true*. If, on the other hand, it is proven false that is just as important (if not more so) and while an understanding of the proof might lead more easily to examples of such, we would know (for certain) that trusting public key encryption over the long run would be a Bad Idea(TM) (for example) and that it is just a matter of time before a polynomial time algorithm is developed.

      (Not that such will necessarily be fast, mind you, but we would know it would exist).

      For another example--there are certain things that can be inferred if Poincare Conjecture is true for N=3. If we can prove the Poincare Conjecture is true (and it is now thought that it might be) it means things to physicists, even if we don't know why it is true.

      The bigger question here is "can we trust it if we can't verify it by hand."

      --
      Integrate Keynote and LaTeX
    7. Re:Create vs. Verify by the_2nd_coming · · Score: 1

      a proof that is to complex for a human to understand or verify?

      is it really a proof then? should a proof not need to be able to be human understandable and verifiable?

      could you not just break it up into lemmas?

      --



      I am the Alpha and the Omega-3
    8. Re:Create vs. Verify by cgenman · · Score: 3, Insightful

      Don't we already have tons of resources devoted to verifying the accuracy of a computing environment? If we verify the logic and accuracy of the computer, much like the axioms of mathematics, cannot we then say that the resulting proof must be valid?

      Of course, if it can't be understood by humans, it doesn't really help anything, as one of the main points of proving things is to gain insight into how to prove other things. But wouldn't building the system to proove proofs be itself a different but valuable tool?

    9. Re:Create vs. Verify by Tower · · Score: 1

      Aside from the people who have enough trouble remembering who they voted for, the people who vote when they are uninformed and choose a large percentage of the ballot somewhat randomly, and those who would love to just mess with the system by intentionally voting opposite on the two machine... yeah... it could work... just not in Florida.

      --
      "It's tough to be bilingual when you get hit in the head."
    10. Re:Create vs. Verify by panaceaa · · Score: 5, Funny

      Fortunately for you software researchers haven't programmed computers to create their own long sentences with so many prepositions that human readers of the created sentences are unable to remember the subject or figure out which verb, or possibly adjective, the trailing adverb applies to by the time they have read the entire sentence yet!

    11. Re:Create vs. Verify by eightheadsofdoom · · Score: 5, Insightful

      That's exactly the case. I had Ken Appel as a professor, and he mentioned the 4-color theorem a couple of times. As he put it, the math wasn't intensive, but actually doing the work the computer was able to do would have taken an army of grad. students years to finish. The way he saw it, the proof was understandable, just extraordinarily, arduously long. That's when they decided to use a computer to solve the problem. Unfortunately, there are still many pure mathematicians who shun computer-based proofs because they (or their grad. students) are not working things out with their own pencils. Unfortunately, I don't think that's a problem that's going away, but I do think it opens up some interesting doors such as writing program A to prove a theorem, and then haveing to prove program A's correctness, for which you write program B and so forth.

    12. Re:Create vs. Verify by Annoying · · Score: 1

      Both can be questioned. Anyone who has taken a calc class has probably seen the calculator return an answer of 3.00000001 or the like from an integration command due to rounding errors. Humans know well enough to doublecheck this if they see it but if it continues onward in the equation those tiny floating point numbers can add up. Also, very few (If any) programs are perfect and it is virtually impossible to write a non-trivial program without bugs.

    13. Re:Create vs. Verify by sisco · · Score: 2, Funny

      "For a famous example, it would provide a great deal of peace of mind if we could prove that P != NP."

      Well, P == NP for N = 1.

      That's the beauty of a counter example.

      --
      DATA comments; PROC SORT DATA = comments BY score; PROC DELETE comments >> 1; RUN; DATA entertainment SET commen
    14. Re:Create vs. Verify by Vancorps · · Score: 1

      It would be like trying to understand the output of a completely computer generated proof! Besides that, it was hard to understand cause of my typo problem with typing words that I don't mean but often start with the same two or three letters.

    15. Re:Create vs. Verify by tomstdenis · · Score: 1

      Your reply had better stay at score:1 cuz it's a bit stupid. As a joke it's lame, if it's not a joke it's REALLY lame.

      Tom

      --
      Someday, I'll have a real sig.
    16. Re:Create vs. Verify by sisco · · Score: 1

      This idea seems like it might work... but what happens when we have verified the comptuers answers up to our limit of ability? We will never know when the computer has pushed past its own limit.

      An example on the simple level is that if you only assign a variable as an integer in C, then it is limited as to the accuracy of calculations your program can make with that specific variable. Whereas, if you use a double float, it is a far more useful variable. Yet, it still has its limits to where at some point it will round off a variable.

      If we aren't sure at what point the computer has pushed its limits, then we have no way of knowing how much we can trust it!

      --
      DATA comments; PROC SORT DATA = comments BY score; PROC DELETE comments >> 1; RUN; DATA entertainment SET commen
    17. Re:Create vs. Verify by cornjones · · Score: 1

      hehehehe
      thanx

    18. Re:Create vs. Verify by Vancorps · · Score: 1

      On the contrary, we can predict when a variable will exceed its container so it would make sense that we could predict when a computer would reach its limits. A human wouldn't have to do the job of predicting, that could be the job of a different type of computer system.

    19. Re:Create vs. Verify by cornjones · · Score: 1

      Isn't this very similar to basic mathematical proofs? Prove it in the simple cases. verify that it works, prove it in the abstract case and move on.

    20. Re:Create vs. Verify by Anonymous Coward · · Score: 0

      Of course Appel and Haken's proof has been simplified since the original version proven by computer. I say this merely to point out that a computer proof doesn't necessarily imply understanding. The best proofs are ones that are coneceptually clean and simple. As far as computer proofs go, I think they are a tool to a mathematician, but no good mathematician would be happy with one. They'd keep going to get at the real concept behind the proof.

    21. Re:Create vs. Verify by Anonymous Coward · · Score: 0

      Holy shit! You finally ditched your karma bonus! Did you lose it, or finally start checking the box?

    22. Re:Create vs. Verify by eliza_effect · · Score: 5, Funny

      Can you please tell us The Question?

      The Ultimate Question?

      Yes!

      Of Life, The Universe..

      And everything?

      And Everything.

      Yes.

      Tricky..

      But can you do it?

      ...No. But I'll tell you who can.

      Who? Tell us!

      I speak of none, but the computer that is to come after me.

      What computer?

      A computer whose merest operational parameters I am not worthy to calculate and yet I will design it for you. A computer which can calculate The Question to the Ultimate Answer. A computer of such infinite and subtle complexity that organic life itself will form part of it's operational matrix. And it will be called.. The Earth.

      What a dull name.

    23. Re:Create vs. Verify by Tablizer · · Score: 1

      Whether or not computers can create proofs isn't an issue. The problem comes when the resulting proof is too involved to be verified by a human, and so the computer's work has to be trusted.

      Just offshore the verification to 1,000 Asian PhD's. *Slap Self* *Slap* *Slap*

    24. Re:Create vs. Verify by Photar · · Score: 1

      The creation of computers with the capability of the creation of hyper-nominalized sentences has the effect of causing the confusion in the readers of the sentences.

      --
      He who knows not and knows he knows not is a wise man. He who knows not and knows not he knows not is a fool.
    25. Re:Create vs. Verify by term8or · · Score: 1

      "The problem comes when the resulting proof is too involved to be verified by a human, and so the computer's work has to be trusted."

      Actually, this is a corollary of an already existing problem. Given the number of mathematical journals each churning out dozens or hundreds of "proofs" every year that are often verified by relatively few experts it is impossible for any mathematician to verify even one percent of existing proofs. This is the reason we rely on peer review (despite the fact that people, including experts, make mistakes and overlook error). The solution may be to find multiple proofs using different software and methods, with spot reviews for random computer generated proofs. The real question is how useful a proof that can't be understood by humans is anyway, since proof (despite what some mathematicians might say) is largely a communications technique to show people (a) the reasoning behind a statement and (b) that the statement seems valid within the current set of axioms and known theorems.

      --



      "As a writer / novelist you might want to spellcheck your sig. :) " - AC
    26. Re:Create vs. Verify by Anonymous Coward · · Score: 0

      The question just boils down to whether or not you can prove the computer program will generate valid proof.

    27. Re:Create vs. Verify by njj · · Score: 4, Interesting

      If we can prove the Poincare Conjecture is true
      OK, yes, that would definitely be worth doing. Various chunks of 3-dimensional geometric topology currently include the caveat ``... if the 3-dimensional Poincare Conjecture is true.''

      (and it is now thought that it might be)
      Depends who you talk to, of course. Perelman reckons he's got an outline proof of Thurston's Geometrisation Conjecture, which implies the Poincare Conjecture as a corollary. But as I understand it he's not actually proved it, just described how one would go about proving it - essentially saying ``It's over the other side of that hill''. Now Perelman is a very bright lad (cleverer than I am) but the Poincare Conjecture has a long history of almost being proved (my research supervisor (I've just finished a PhD in algebraic and geometric topology) almost did it about twenty years ago, for example, but there was a very subtle and unresolvable flaw in his argument) so I'm going to reserve judgement until the paper turns up in the Annals of Mathematics.

      I wouldn't be surprised if the Conjecture turned out to be true, as the corresponding result is known to be true in dimensions 1,2,4,5,... (well, to be picky, the smooth 4-dimensional case hasn't been proved yet, but the topological and piecewise-linear ones have). But equally, I wouldn't be shocked if it weren't - 3-dimensional topology is a weird subject, as there's enough room to start discussing interesting things, but there's not so much room that everything trivialises.

      Quick precis of the Conjecture:
      ``If it looks like a sphere, it is''.

      Slightly less quick precis of the Conjecture:
      Given any topological space X, we can assign a sequence of groups (`homotopy groups') pi_n(X) to it, so that pi_n(X) in some sense describes the n-dimensional structure of X. An n-manifold (a topological space which locally `looks like' ordinary, flat n-dimensional space) which has the same sequence of homotopy groups as the 3-dimensional sphere, is called a `homotopy 3-sphere'. The Poincare Conjecture is that the 3-sphere itself is the only homotopy 3-sphere.

      So, to prove it, we have to show that every homotopy 3-sphere is topologically equivalent (`homeomorphic') to the 3-sphere. And to disprove it, we just have to find one counterexample - a homotopy 3-sphere which isn't equivalent to the 3-sphere itself.

      Now to use a computer to prove the Conjecture, we need to find some way of verifying that every possible homotopy 3-sphere is equivalent to the 3-sphere. This is theoretically doable - there's an algorithm (the Rego-Rourke algorithm) which lists (with redundancy), all possible homotopy 3-spheres. There's another algorithm (the Rubenstein-Thompson algorithm) which, given a homotopy 3-sphere, can tell if it is equivalent to the 3-sphere. So in theory we just feed the output of the RRA into the RTA.

      Except that there are an infinite number of possible homotopy 3-spheres to check, so if the Conjecture is true, this program will never terminate.

      Now if you can find some way of reducing the cases under consideration to some finite subset (by, for example, showing that all but a finite number of homotopy 3-spheres obviously satisfy the conjecture) then using a computer suddenly becomes a worthwhile endeavour. This is basically what Appel and Haken did with the Four-Colour Map Theorem.

      The computer approach is also useful for searching for counterexamples, and for verifying that all cases up to some level of complexity satisfy the Conjecture.

      But where computers aren't currently going to help, is in the actual creative side of things - a lot of important modern mathematics (and the related theorems and proofs) has come from very clever humans saying ``OK, what happens if we try this (utterly weird and counterintuitive) thing here'' and having the aesthetic sense to tell when something's actually interesting or just irrelevant. Until computers are capable of this kind of creative/intuitive/aesthetic/etc behaviour, I doubt they're going to be replacing human research mathematicians any time soon.

      nicholas

    28. Re:Create vs. Verify by pjt33 · · Score: 1
      If humans created the computer to do the task should they not trust that it would do the task and do it well? Perhaps, perhaps not.
      No large program is bug-free.
    29. Re:Create vs. Verify by tomstdenis · · Score: 1

      I lost it on one of my "flamepaths". Good riddance though. I was all high and mighty posting at +2 all the time...

      Tom

      --
      Someday, I'll have a real sig.
    30. Re:Create vs. Verify by BigBadBri · · Score: 1
      Apart from in German speakers, that is.

      --
      oh brave new world, that has such people in it!
    31. Re:Create vs. Verify by Anonymous Coward · · Score: 0

      You suck!

    32. Re:Create vs. Verify by tomstdenis · · Score: 1

      Um dude, that's what I was trying to say.

      I mod you -1, rerun

      --
      Someday, I'll have a real sig.
    33. Re:Create vs. Verify by Anonymous Coward · · Score: 0
      Unfortunately, there are still many pure mathematicians who shun computer-based proofs because they (or their grad. students) are not working things out with their own pencils.


      Clearly, these mathematicians are constipated.
    34. Re:Create vs. Verify by Jagasian · · Score: 1

      Tell that to constructivists, to whom there is no truth, only proof.

    35. Re:Create vs. Verify by Vancorps · · Score: 1

      No one said it was large, only that it performed a certain task. There are plenty of programs that perform one or two, even 50 tasks without having bugs in them. Medical monitoring equipment would be a good example. Besides that, with enough time you can make pretty well anything bug free, especially if you design it from the ground up logically which is where many software designers go wrong.

    36. Re:Create vs. Verify by PantsWearer · · Score: 1
      But where computers aren't currently going to help, is in the actual creative side of things - a lot of important modern mathematics (and the related theorems and proofs) has come from very clever humans saying ``OK, what happens if we try this (utterly weird and counterintuitive) thing here'' and having the aesthetic sense to tell when something's actually interesting or just irrelevant. Until computers are capable of this kind of creative/intuitive/aesthetic/etc behaviour, I doubt they're going to be replacing human research mathematicians any time soon.

      I don't see this as much of a problem. Computers have no "intuition" at all. In fact, modern automated provers basically just run down every path offered them whether it leads anywhere or not, which is how they've come up with novel proofs for things that have already been proven by another method. It comes down to a human not having thought of it, but the computer stumbled into it.

      Computers have the advantage of speed. They can go through some huge number of completely useless proofs in a reasonably short time. Given enough time and horsepower, they can find all of the "utterly weird and counterintuitive" things that lead to great discoveries. Their current state isn't very good, but, as everyone here knows, they keep getting faster, even if we don't know what to do with them.

      --
      Be glad life is unfair, otherwise we'd deserve all this.
    37. Re:Create vs. Verify by stupid_is · · Score: 1

      As it happens, a bunch of mathematicians with waaay too much time on their hands are going through the computer proof by hand. I'm sure that'll make for interesting reading when it comes out. I found this out courtesy of the Annals of Improbable Research - invaluable background reading to be found at www.improbable.com , highlighed in their email summary mailing.

      --
      -- Intelligence is soluble in alcohol
    38. Re:Create vs. Verify by Anonymous Coward · · Score: 0

      You suck!

  5. 'Can we trust the darned things?' by FFFish · · Score: 4, Funny

    Depends whether it's a Pentium with an FDIV bug, I imagine...

    --

    --
    Don't like it? Respond with words, not karma.
    1. Re:'Can we trust the darned things?' by Anonymous Coward · · Score: 0

      Intel, the microchip giant, uses proof-checking software to check algorithms in its chips, in the hope of avoiding glitches like one in the original 1994 Pentium that caused numbers to divide incorrectly.

      Can we trust the software that tells us the chip design is sound?

    2. Re:'Can we trust the darned things?' by Anonymous Coward · · Score: 1, Interesting

      True. Any argument is only as good as it's assumptions.

      You may find the following project interesting:
      It [acl2] is a common lisp programming language and a system for proving properties about code. It has been used to prove correctness properties about microprocessors[microcode], compilers, and application code. Notably, I believe it is currently being used to prove certain properties about the Java Sandbox.

      When the FDIV bug was reported, AMD hired it's creators to mechanically verify correctness of it's floating point microcode on a model of the K5 developed on the system. Details

      In fact, they were unable to verify it's correctness, as it wasn't correct. Fortunately, the code was able to be changed, prior to chip fabrication, saving AMD a lot of money and a lot of embarassment.

    3. Re:'Can we trust the darned things?' by Anonymous Coward · · Score: 2, Insightful

      You know what? I work for Intel. My company paid 1/2 billion dollars replacing Pentium chips with that bug that nobody would ever notice except maybe six people. Software vendors get away with murder. They don't even have to replace their product even if it is not fit for it's stated purpose. The FDIV bug was a typo in some kind of table. Doesn't that make it software in a way? One little bug years ago and still people laugh about it (SCORE:4, Funny).

    4. Re:'Can we trust the darned things?' by Anonymous Coward · · Score: 0

      It's a good thing we're hitting these phenomenon at the height of their popularity. Got any Windows 95 jokes?

      -Stolen from Stewie

    5. Re:'Can we trust the darned things?' by Anonymous Coward · · Score: 0

      Reminds me of a famous line... "I'm not trusting our nation's security to that see-lee-con diode over there..."

    6. Re:'Can we trust the darned things?' by achurch · · Score: 1

      I work for Intel. My company paid 1/2 billion dollars replacing Pentium chips with that bug that nobody would ever notice except maybe six people. Software vendors get away with murder. They don't even have to replace their product even if it is not fit for it's stated purpose.

      Maybe you could help by introducing your methodology to the programming community? No, really--if you can make things as complex as CPUs with as few bugs as they have, then I think software developers could learn a lot from the processes you use. Granted, there's a whole bunch of momentum saying "it's okay for software to suck" that needs to be turned around, but every little bit helps. (And I don't know how applicable hardware development processes are to software--I plead ignorance--but chips that just work have to count for something...)

    7. Re:'Can we trust the darned things?' by fred+fleenblat · · Score: 1

      (a) Intel actively lied about the presence of the FDIV bug and dug their own PR grave.

      (b) firmware on Pentiums isn't field upgradeable and therefore has a higher standard to live up to.

      (c) long division is not new and is easy to test and should have been tested by a fourth grader at least.

      (d) I really don't think intel spent 1/2 billion dollars of real hard cash replacing chips that depreciated to $10 in a matter of months and only cost $5 to manufacture. the fix was trivial and certainly didn't deserve a big amortization share of Intel's galactic R&D budget either.

      What they should have done differently?
      Admit the bug as soon as reports came in, offer to replace the chip free for anyone with scientific computing needs, distribute a math DLL that intercepts the FDIV call in software and replaces the results with correct ones. And offer at-cost replacements to anyone not happy with the DLL.

  6. Will this complicate what we can understand? by Anonymous Coward · · Score: 3, Interesting

    I think the issue will become: can we learn anything on our own, we don't want to rely on imposibly long proofs. My calc teacher hates us using calculators, she thinks it will be the end of calculus as we know it.

    1. Re:Will this complicate what we can understand? by iminplaya · · Score: 1

      My calc teacher hates us using calculators...

      So do I. They should be banned from school, just like guns. It's one thing to use them in business for quick work. They have no place in school where you're supposed to be learning how to add.

      --
      What?
    2. Re:Will this complicate what we can understand? by Knetzar · · Score: 1

      After algebra, one should do most calculations with variables in the result. The area of a circle with a radius of 3 is simply 9*pi, on a test why does it matter if the student plugs the number in to get a decimal number?

    3. Re:Will this complicate what we can understand? by pastafazou · · Score: 1

      Simple. The student should know the value of pi to a certain number of significant figures. With a calculator, they're just typing in 3*pi and getting an answer with 8+ significant digits. Without a calculator, they're actually calculating the answer as close as they can based on how many significant digits they know. That's a better test of who's mastering mathematics.

    4. Re:Will this complicate what we can understand? by iminplaya · · Score: 1

      The area of a circle with a radius of 3 is simply 9*pi, on a test why does it matter if the student plugs the number in to get a decimal number?

      Because you're just repeating the formula. The answer is single number, real or otherwise. I need to know the actual area of the circle, not the formula for figuring it out.

      --
      What?
    5. Re:Will this complicate what we can understand? by Anonymous Coward · · Score: 0

      Here is a comprimise:

      I will gladly abstain from using a calculator the day I am not given pages and pages of redundant math assignments to do.

    6. Re:Will this complicate what we can understand? by Absurd+Being · · Score: 1

      Sure, I'll just leave behind 8*pi*e^(jpi/6) * (3*10^8)^3 /(1.602*10^-19 * (1.5)^.5 *2^.5*(4pi*10^-12^2)) as my answer. Or I could just give you a number. It's all constants and variables, just a boatload of them together.

      --
      Karma: Excellent^(-t/Tau), Tau=Wittiness/Trollishness
    7. Re:Will this complicate what we can understand? by jdhutchins · · Score: 1

      Beyond algebra, the point of the test is not to test arithmetic skills, it's to test whatever area you're learning. By the time you learn algebra, you've spent roughly 6-8 years learning arithmetic, so there's not much point in beating it out of you any more. You know how to do it, it's just a matter of how many careless mistakes you make.

      For some tests, you shouldn't be allowed to use a calculator (knowing basic sine and cosine values, for example, or numerical integration without a calculator). Other than that, you're just seeing how few careless mistakes the student is making over stuff they've already been tested on, which is not always the point of the test.

    8. Re:Will this complicate what we can understand? by Xilo · · Score: 1

      In the real world, 9pi isn't very often a totally valid number. How much material do I need to cover this circular area? "Oh yes, supply co., I'm going to need 9pi square yards (or miles, or kms, or rods..) of your highest quality ____. Thank you!"
      Plugging in the numbers allows the students to see if the resulting number is a reasonable answer, secondly. That's a pretty crucial step, especially on a test. If your algebraic answer is 325x**2, that doesn't tell you nearly as much as the decimal equivalent.

      --
      Read; Write; Execute
    9. Re:Will this complicate what we can understand? by DoraLives · · Score: 1
      "The bridge fell during rush hour!"

      "The engineering calculations were all wrong!!"

      "Yeah, but it was only a careless mistake in arithmetic, so there's no real harm done."

      --
      Is it fascism yet?
    10. Re:Will this complicate what we can understand? by djplurvert · · Score: 2, Insightful

      If you are still trying to learn how to add in calculus class then there are bigger problems.

      It is one thing to deride the use of cacluators because they are crutches, it is another thing altogether to deride them because you are a technophobe.

      Technology is extremely useful in aiding understanding and exploration of mathematics. If you eliminate calculators and computers in schools, even high schools, you may hurt the chances of your students to succeed in an increasingly technical world.

      As usual, I think the correct response is a balanced response. Demonstrate how to use technology as a tool and provide assessment that requires demonstration of ability without the use of a calculator as a crutch.

      In a calculus class, for example, divide the exams into two parts, or alternate between calculator allowed, and calculator disallowed exams.

      Of course, this has little to nothing to do with the nytimes article but it always seems to come up in these discussions.

      plurvert

    11. Re:Will this complicate what we can understand? by Loconut1389 · · Score: 1

      redundancy and repetition is the path to remembering.

    12. Re:Will this complicate what we can understand? by Lehk228 · · Score: 1

      My calc teacher hates us using calculators, she thinks it will be the end of calculus as we know it.
      And I pray to $DEITY that she is correct

      --
      Snowden and Manning are heroes.
    13. Re:Will this complicate what we can understand? by Knetzar · · Score: 1

      Most of my favoite professors would require the answer to be simplified a bit more then that, I mean (96*10^187)*(pi^2)*e^(jpi/6)*(1.602) / ((1.5)^.5 *(2^.5)) is an acceptable answer, and simplified enough.
      Also where did the 1.602 come from? Chances are it's a constant in the problem, such as the mass of some object, so my answer would be (96m*10^187)*(pi^2)*e^(jpi/6) / ((1.5)^.5 *(2^.5)).

    14. Re:Will this complicate what we can understand? by Knetzar · · Score: 1

      saying you need 28.274333882308139146163790449516 cm^2 of material doesn't really help you either. If your covering a circular area you need to worry about fully covering it, chances are your going to get a large amount of material and cut it into the correct size, in which case you need a square with a side = 6cm, and you need to know that the circle has a radius of 3cm.

    15. Re:Will this complicate what we can understand? by Knetzar · · Score: 1

      when you get to calculas and beyond, do you really need to bother doing basic long division?

    16. Re:Will this complicate what we can understand? by bluGill · · Score: 1

      Why should guns be banned from school? Serious question, why? Forget about the bad guys, they are going to break the rules anyway, so whats the point in keeping good guys away from guns?

      Yes this is on topic: why should calculators be banned from math? Once again something that sounds good, but requires more thought. In truth, higher math like algebra is normally done on contrived problems where the math is easier and faster to do in your head. (and you learn that if you can't do the math in your head to re-do some earlier work as you likely made a mistake) In cases where the math isn't easy give the kid a calculator and let him worry about the problem instead of of carrying the 1...

      Challenge all assumptions. Sometimes they have a good reason, but don't state them as facts unless you are prepared to back them up. You will encounter people like me who don't see the point in keeping guns our of schools.

    17. Re:Will this complicate what we can understand? by Anonymous Coward · · Score: 0

      Pi is not a freaking variable, all you kiddies are talking like Pi is some mystical variable dangit, e and Pi are numbers. If I say 9*Pi+e^(Pi/2) thats exactly the same as 33.0848....

    18. Re:Will this complicate what we can understand? by slimak · · Score: 1

      even better, polynomial division - not real advanced, but pretty painful for even low-order polynomials.

    19. Re:Will this complicate what we can understand? by NichG · · Score: 1

      1.602x10^-19 is the charge of an electron in coulombs (or the conversion factor between joules and eV).

      The 3x10^8 is the speed of light in meters. I'm not sure what the 10^-12 would be here, but it's probably something like the permittivity of free space since this looks a lot like some EM calculation.

      You've got a sqrt(3) in there, and e^(j pi/6) is j/2 + sqrt(3)/2 so those are going to cancel out somewhat if you end up taking the real part.

      Of course it could all be arbitrarily chosen random stuff, since he didn't give what the actual constants are.

      Leaving all the variables means you actually know more about your answer than collapsing it into one big number. It means you can change units (same is true if you keep track of units) and know what part of your answer is based on exact fundamental constants and what part is based on some odd coincidence (314/100 != pi)

      The best bet is to define symbols for all the fundamental constants of the problem, and then do the problem in units such that those symbols evaluate to 1, so then you have an answer which is cleanly separated between the stuff that scales and the stuff which is due to geometry/the specifics of your problem (cylinder as opposed to ellipsoid or sphere or cube with a hyperbola cut out of it)

    20. Re:Will this complicate what we can understand? by cubic6 · · Score: 1

      Remembering digits of pi means absolutely nothing to "mastering mathematics."

      --
      Karma: Contrapositive
    21. Re:Will this complicate what we can understand? by cubic6 · · Score: 1

      That's why engineers should use calculators.

      --
      Karma: Contrapositive
    22. Re:Will this complicate what we can understand? by azaris · · Score: 2, Insightful

      Simple. The student should know the value of pi to a certain number of significant figures.

      Why? Einstein was once asked how many digits of Pi he could remember. He replied "maybe three or four". The interviewer then exclaimed: "But Sir, some people have memorized hundreds of digits!" Einstein's reply was: "Ah, but I know where to look them up if I need them."

      With a calculator, they're just typing in 3*pi and getting an answer with 8+ significant digits. Without a calculator, they're actually calculating the answer as close as they can based on how many significant digits they know.

      Wrong, wrong, wrong. If the answer to some problem is 9 Pi then the answer to that problem is 9 Pi, not 28.274333882308139146163790449516.

      That's a better test of who's mastering mathematics.

      Memorizing Pi and doing multiplication on paper has almost no relevance at all to "mastering mathematics".

    23. Re:Will this complicate what we can understand? by RackinFrackin · · Score: 1

      The answer is single number, real or otherwise.

      Yes. And that number is 9*pi. Anything written using decimals is an approximation.

    24. Re:Will this complicate what we can understand? by Loconut1389 · · Score: 1

      well ive been using basic long division in a few classes at the 300 and 400 level maths.. it seems that they like to take your calculators away from you eventually, and then like to make you do things like find primes, gcd's, lcm's etc.. They show you some algorithms to help, but still a lot of division without calculators!

    25. Re:Will this complicate what we can understand? by Absurd+Being · · Score: 1

      Yeah, eps0 is that factor of 10^-12. This is part of a calculation to find laser gain, but I didn't remember it exactly, and I think I still forgot a lambda squared term in there, and g(nu). This isn't arbitrarily chosen stuff, I've used this at least once before. You can also change a number from units set to units set if you keep in mind what the units are, multiplying a number by 1/6.25*10^18, for instance, turns eV into joules just as effectively as keeping everything in terms of variables and constants and multiplying by that factor.

      As for keeping everything as integir multiples of some fundamental units, aren't there enough ****ing units out there already? How many mars probes crashing due to a conversion error do you need to have happen? Sure, I could define all the constants as just 1 'foo' unit, but keeping track of that unit would be a nightmare for actually using this formula.

      --
      Karma: Excellent^(-t/Tau), Tau=Wittiness/Trollishness
    26. Re:Will this complicate what we can understand? by Anonymous Coward · · Score: 0

      Ah... this reminds me when I was in HS, and we had our trig test. Five problems in 45 minutes, so they weren't that easy. I got them all, and due to the fact that this was the first calculator-allowed test ever, we were passing different models around before the test. During that passing around and pressing the keys, somebody switched my calc to radians, and I got all the computations wrong. Got it right up to the very last line, i.e., x=sin(47degrees), but that last computed result was wrong.
      The result: a C on that test.
      From that day on, I never wanted to see calculators in classrooms. There were tests where I just didn't use mine, and finished faster and more accurately than others who did. Went through three calcs + DiffEq without one... f**king calculators.

    27. Re:Will this complicate what we can understand? by Xilo · · Score: 1

      ok, for a uniform, solid material. What about for.. water? you have a round swimming pool that's however many feet deep, and you're trying to find the volume? Or for an art thing, you're trying buy enough BBs (the little metal sphere one shoots) to fill a cylindrical container a foot high?

      --
      Read; Write; Execute
    28. Re:Will this complicate what we can understand? by iminplaya · · Score: 1

      Why should guns be banned from school?

      For all the obvious reasons. Think about it, seriously.

      ...why should calculators be banned from math?

      Because you are there to work your brain. That's what school is supposed to be about. Hell, if it was up to me, I would ban pencils and paper, and make you work it out in your head (just kidding). Calculators are fine at work, where time is money, but in school, learning is money in your pocket, even though you won't realize it until much later.

      --
      What?
    29. Re:Will this complicate what we can understand? by Knetzar · · Score: 1

      for a swimming pool your right, knowing the volume of the pool is needed to order the correct amount of material, but for filling a cylinder w/ BBs there is a lot more to deal with then knowing the volume of the cylinder. You need to consider if the BBs will be too big to even fit (1cm BBs, and 4mm radius cylinder), and how well the BBs will pack (wow, we're back on topic). If your trying to do something that complicated, use a calculator to come up with a single number, but at least make that your last step.

    30. Re:Will this complicate what we can understand? by bluGill · · Score: 1

      Why should guns be banned from school? For all the obvious reasons. Think about it, seriously.

      I have thought about it seriously. I can not come up with a good reason to ban guns from schools. Remember the "bad guys" ignore laws, so all we the ban does is restrict the law abiding people from having a gun around. Reasons to have a gun in school: target practice, which should be a part of gym class, just like archery is (at least it was in my school). Then there is protection, if a bad guys brings a gun to school and starts shooting the only good way to stop them is to shoot back, which the "good guys" won't be doing if they don't have a gun. Yes, accidents can happen, but accidents can happen otherwise too. There are more guns than people in the US, yet almost nobody dies in a gun accident (a few every year), drowning is more likely to kill you. Sure there are a lot of murders committed with guns, but that isn't the fault of the tool.

      My brain is to think. I can spend a few minutes multiplying 1526.86 * 93477.193 or I can get the answer in moments from my calculator. Now if the problem is fourth grade math, yes I should be doing it with paper and a pencil, but if the problem comes up in forth grade science from some experiment my time is better spent understanding the problem at hand. I already proved in math that I can get the right answer (or worse proved I can't, and now my math lacks are going to take down my science score) so I'm better off spending the time understanding the science behind those numbers than the math behind it.

    31. Re:Will this complicate what we can understand? by iminplaya · · Score: 1

      ...drowning is more likely to kill you.

      Then we should ban di-hydrogen monoxide from the schools also. :-)

      I think somebody did an animal experiment where they covered up the eyes since birth, so that part of the brain normally used for sight went on to do "other things". When they took the blinders off, the animal remained blind, because there was literally nothing "wired" to the eyes anymore. My point being that if you don't use your brain, it will get "flabby". You'll find yourself forgetting how to do things. Until you finish high school, you need to be well rounded in all aspects (of math in this case). When you start to specialize in a specific field, go nuts and use all the tools at your disposal.

      --
      What?
    32. Re:Will this complicate what we can understand? by Josh+Booth · · Score: 1

      For the purposes of math, it is irrelevant what the evaluated, and many times approximate, answer is. Only engineers and physicsist and people who have to interact with the real world need to worry about evaluating the expression. And with a lesser calculator, like the Ti-83 ('89's are too smart), it shows that you didn't just ask the almighty calculator.

  7. Well... by -kertrats- · · Score: 1

    Well, we certainly can't trust them to let us read the article. Anyone got a registration handy?

    --
    The Braying and Neighing of Barnyard Animals Follows.
    1. Re:Well... by Russellkhan · · Score: 1

      How about this: a Google partner link to the story - no registration required.

      --
      Information doesn't want to be anthropomorphized anymore.
  8. I think so, yes. by James+A.+M.+Joyce · · Score: 3, Informative

    I mean, we've used computers to prove much of boolean and linear algebra. The most famed result in the field is that of the Robbins Conjecture, proven entirely by computer. The computer produced a very "inhuman" proof...

    1. Re:I think so, yes. by Quill345 · · Score: 5, Insightful

      Automated theorem provers have been around for a long time, if you can express your thoughts using first order logic. Here's a program from 1986... lisp code

    2. Re:I think so, yes. by snarkh · · Score: 1

      Much of linear algebra? What basis do you have for saying that, except for that conjecture, which is rather marginal, after all.

    3. Re:I think so, yes. by sl956 · · Score: 1
      I mean, we've used computers to prove much of boolean and linear algebra. The most famed result in the field is that of the Robbins Conjecture, proven entirely by computer. The computer produced a very "inhuman" proof...
      I disagree. Trust was not involved for the Robbins Conjecture: the proof was only "inhuman" in the sense that it would have been very difficult for someone to find it. But it was dead simple to verify that proof once the computer had found it.
      The problem we have now is that some proofs generated by computers are too big or too complex to be verified by humans. Here lies the problem of trust.
  9. It was a big help with the 4-color map proof... by The+Beezer · · Score: 5, Informative

    and there are already programs out that help with this. Here's one for example...

    1. Re:It was a big help with the 4-color map proof... by kfg · · Score: 1

      Yes, but isn't the four color problem exactly an example of what the article is about? The last time I looked it had never been fully human verified.

      KFG

  10. Next thing you know.... by Anonymous Coward · · Score: 1, Funny

    there will be a computer that will automatically post on slashdot.

    1. Re:Next thing you know.... by UserAlreadyExists · · Score: 1

      there will be a computer that will automatically post on slashdot.

      Actually, I'm working on a Hidden Markov Model program to generate typical slashdot comments. So, yes, you're right.

      --
      "Screw causalilty!" -- Prof. Farnsworth
    2. Re:Next thing you know.... by Anonymous Coward · · Score: 0

      We already have those. They're called 'slashbots'. You can see them making insensitive clod posts in polls, flaming Microsoft or praising Linux.

    3. Re:Next thing you know.... by PrintError · · Score: 1

      Will that replace the one they have that automatically double posts articles once a month?

  11. Text of the article by Anonymous Coward · · Score: 2, Informative


    In Math, Computers Don't Lie. Or Do They?
    By KENNETH CHANG

    Published: April 6, 2004

    leading mathematics journal has finally accepted that one of the longest-standing problems in the field -- the most efficient way to pack oranges -- has been conclusively solved.

    That is, if you believe a computer.

    The answer is what experts -- and grocers -- have long suspected: stacked as a pyramid. That allows each layer of oranges to sit lower, in the hollows of the layer below, and take up less space than if the oranges sat directly on top of each other.

    While that appeared to be the correct answer, no one offered a convincing mathematical proof until 1998 -- and even then people were not entirely convinced.

    For six years, mathematicians have pored over hundreds of pages of a paper by Dr. Thomas C. Hales, a professor of mathematics at the University of Pittsburgh.

    But Dr. Hales's proof of the problem, known as the Kepler Conjecture, hinges on a complex series of computer calculations, too many and too tedious for mathematicians reviewing his paper to check by hand.

    Believing it thus, at some level, requires faith that the computer performed the calculations flawlessly, without any programming bugs. For a field that trades in dispassionate logic and supposedly unambiguous truths and falsehoods, that is an uncomfortably gray in-between.

    Because of the ambiguities, the journal, the prestigious Annals of Mathematics, has decided to publish only the theoretical parts of the proof, which have been checked in the traditional manner. A more specialized journal, Discrete and Computational Geometry, will publish the computer sections.

    The decision represents a compromise between wholehearted acceptance and rejection of the computer techniques that are becoming more common in mathematics.

    The debate over computer-assisted proofs is the high-end version of arguments over using calculators in math classes -- whether technology spurs greater achievements by speeding rote calculations or deprives people of fundamentals.

    "I don't like them, because you sort of don't feel you understand what's going on," said Dr. John H. Conway, a math professor at Princeton. But other mathematicians see a major boon: just as the computers of today can beat the grand masters of chess, the computers of tomorrow may be able to discover proofs that have eluded the grandest of mathematicians.

    The packing problem dates at least to the 1590's, when Sir Walter Raleigh, stocking his ship for an expedition, wondered if there was a quick way to calculate the number of cannonballs in a stack based on its height. His assistant, Thomas Harriot, came up with the requested equation.

    Years later, Harriot mentioned the problem to Johannes Kepler, the astronomer who had deduced the movement of planets. Kepler concluded that the pyramid was most efficient. (An alternative arrangement, with each layer of spheres laid out in a honeycomb pattern, is equally efficient, but not better.) But Kepler offered no proof.

    A rigorous proof, a notion first set forth by Euclid around 300 B.C., is a progression of logic, starting from assumptions and arriving at a conclusion. If the chain is correct, the proof is true. If not, it is wrong.

    But a proof is sometimes a fuzzy concept, subject to whim and personality. Almost no published proof contains every step; there are just too many.

    The Kepler Conjecture is also not the first proof to rely on computers. In 1976, Dr. Wolfgang Haken and Dr. Kenneth Appel of the University of Illinois used computer calculations in a proof of the four-color theorem, which states that any map needs only four colors to ensure that no adjacent regions are the same color.

    The work was published -- and mathematicians began finding mistakes in it. In each case, Dr. Haken and Dr. Appel quickly fixed the error. But, "To many mathematicians, this left a very bad taste," said Dr. Robert D. MacPherson, an Annals editor.,

    To a

  12. I see no good reason why not.... by kommakazi · · Score: 4, Interesting

    Computers are a human creation...it's not a matter of whether we can trust the computer, but rather a matter of can we trust that the people who built the computer and coded the software it runs knew what they were doing and didn't make any errors. Computers can only do what we tell them to...so really it was humans who indirectly made the proofs by producing a system capable of doing so. All it really boils down to is whether the folks who made the system and it's software knew what they were doing or not and whether they made any errors or not.

    1. Re:I see no good reason why not.... by wmspringer · · Score: 1

      And if you trust that the computer didn't break...though I suppose you can always get the software and run it on your old computer.

      I had a calculator once that started giving wrong answers in the middle of a math test; very inconvenient :-p

    2. Re:I see no good reason why not.... by iminplaya · · Score: 1

      It boils down to the old cliche, "Garbage in, garbage out."

      --
      What?
    3. Re:I see no good reason why not.... by wmspringer · · Score: 1

      er, owN computer, sorry

    4. Re:I see no good reason why not.... by Hao+Wu · · Score: 0, Offtopic
      Computers are a human creation...it's not a matter of whether we can trust the computer, but rather a matter of can we trust that the people who built the computer and coded the software it runs knew what they were doing and didn't make any errors. Computers can only do what we tell them to...so really it was humans who indirectly made the proofs by producing a system capable of doing so.

      Completely fascinating.... So how do I use a mouse? Also, I wish to use 3.5" disk in my 5.25" floppy drive.. is this possible?

      --
      I suggest you read Slashdot
    5. Re:I see no good reason why not.... by dangermouse · · Score: 1
      Completely fascinating.... So how do I use a mouse? Also, I wish to use 3.5" disk in my 5.25" floppy drive.. is this possible?

      I've spent five minutes trying to determine not only your point, but what possible relevance these comments can have to the text you quoted. So I thought maybe I should just ask: What in the hell are you talking about?

    6. Re:I see no good reason why not.... by Rosyna · · Score: 2, Insightful

      See the problem is humans can only program a computer to do something the human coding it knows how to thoroughly describe. It is also why you won't see a computer naturally speaking, showing emotions, or doing anything else we cannot describe today.

      It is amusing to see computers being used as proof bringers when you usually need a proof to program the darn things.

    7. Re:I see no good reason why not.... by Sunlighter · · Score: 1

      Actually, the program that generates the proof might be much shorter and easier to verify than the proof it generates.

      Running it on lots of different hardware, and getting the same result, should provide some confidence that there were no errors in the hardware which affected the computation.

      It would also be possible to re-run the proof on special, simplified hardware, which is easier to verify.

      What you are saying is that we have a science of men and not of laws. I think not. The laws still work, we just have to dig a little bit more to find them.

      --
      Sunlit World Scheme. Weird and different.
    8. Re:I see no good reason why not.... by ortholattice · · Score: 1
      The trust that can be placed in a computer-verified proof is no more and no less than the trust in the program that does the verification. That computer program must be correct; if it is, then the verified proof is a close to being absolutely correct and rigorous as is humanly and theoretically possible. So that program is the one thing that must be bug-free. Bugs or errors in the proof itself are impossible by definition if the verifier is bug-free. (If a bad proof can slip by the verifier then that is a bug in the verifier.)

      Some proof-verification languages require verification programs that are rather large. For example, it has been estimated that a minimal verifier for HOL (a relatively light verification language) would require about 3000 lines of Python code for a verifier. Two projects that have significantly more modest requirements for their checking code are Ghilbert (currently in its early stages) and Metamath (more mature but with the drawback that new definitions can only be introduced as new axioms and therefore must be manually checked for soundness). A proof verifier has been written for the latter with only 300 lines of Python code.

    9. Re:I see no good reason why not.... by Anonymous Coward · · Score: 0

      I think its funny people are debating whether man made logic machines are capable of running logical analysis of logic better than humans. If mathematicians could mathematize the error checking, they would, because thats what mathematicians do. Logicians, whether proving with computers, programming computers to prove, or checking computer proofs with computers are still applying logical algorithms the same way as computers are.

  13. I always loved this picture by DanThe1Man · · Score: 1

    do you mean that this picture will be true someday? It does seem a lot friendlier then SKYNET.

    1. Re:I always loved this picture by corngrower · · Score: 1

      If you've developed software with something like Visual C++, you've probably used 'Wizards'. They essentialy do what you see in the picture. You give the wizard some basic information. It spits out bunches of code.

  14. no by sporty · · Score: 2, Funny

    no.

    q.e.d.

    --

    -
    ping -f 255.255.255.255 # if only

    1. Re:no by Anonymous Coward · · Score: 0

      You're one of those people who thought computers would never be able to play chess, right?

  15. Theorem Provers by bsd4me · · Score: 4, Informative

    Theorem provers have been around for a long time. A net search should turn up a ton of hits. The key is to implement a system that can be verified by hand, and then build on it.

    --

    (S(SKK)(SKK))(S(SKK)(SKK))

  16. new facet of an old issue by colmore · · Score: 5, Insightful

    20th century mathematics has seen some pretty amazing things, but at the same time, there are very real questions as to what constitutes "proof" any more.

    consider this: the hypothesis of the famous Riemann Zeta problem has been tested for trillions of different solutions, and it has held true in every case. (If you want an explanation of the Zeta problem, look elsewhere, I don't have the time)

    Now that means that it's *probably* true, but nobody accepts that as mathematical proof.

    On the other hand, the classification problem for finite simple groups has been rigorously solved, but the collected proof (done in bits by hundreds of mathematicians working over 30 years) is tens of thousands of pages in many different journals. given the standards of review, it is a virtual certainty that there is an error somewhere in there that hasn't been found. So, again, the solution to this problem is *probably* right, but it has been accepted as solved.

    What's the difference between these two cases really? What's the difference between these and relying on computer proofs that are, again, *probably* right?

    In this light, the math of the late 19th century and early 20th century was something of a golden age, modern standards of logical rigor were in place, but the big breakthroughs were still using elementary enough techniques that the proofs could be written in only a few pages, and the majority of mathematically literate readers could be expected to follow along. These days proofs run in the hundreds of pages and only a handful of hyper-specialized readers can be expected to understand, much less review them.

    --
    In Capitalist America, bank robs you!
    1. Re:new facet of an old issue by qbwiz · · Score: 2, Interesting

      On the other hand, the classification problem for finite simple groups has been rigorously solved, but the collected proof (done in bits by hundreds of mathematicians working over 30 years) is tens of thousands of pages in many different journals. given the standards of review, it is a virtual certainty that there is an error somewhere in there that hasn't been found. So, again, the solution to this problem is *probably* right, but it has been accepted as solved.

      Wouldn't this be a good use for the computer, then - attempting to verify these disjointed proofs and combine them into one unified whole?

      --
      Ewige Blumenkraft.
    2. Re:new facet of an old issue by Anonymous Coward · · Score: 0

      why smug bastards?

    3. Re:new facet of an old issue by Anonymous Coward · · Score: 0

      Yea, you are probably right.

    4. Re:new facet of an old issue by I+Be+Hatin' · · Score: 5, Insightful
      consider this: the hypothesis of the famous Riemann Zeta problem has been tested for trillions of different solutions, and it has held true in every case. (If you want an explanation of the Zeta problem, look elsewhere, I don't have the time) Now that means that it's *probably* true, but nobody accepts that as mathematical proof.
      On the other hand, the classification problem for finite simple groups has been rigorously solved, but the collected proof (done in bits by hundreds of mathematicians working over 30 years) is tens of thousands of pages in many different journals. given the standards of review, it is a virtual certainty that there is an error somewhere in there that hasn't been found. So, again, the solution to this problem is *probably* right, but it has been accepted as solved.
      What's the difference between these two cases really?

      That one claims to be a proof and the other doesn't? You simply can't prove the Riemann Hypothesis by testing trillions of numbers (though if you find one case where it fails, you have disproved it). As a simple example, I can find trillions of numbers whose base-10 expansion is less than a googolplex digits long. Does this mean that all integers have this property? Of course not... So even if all of the calculations are right, you still don't have a proof.

      On the other hand, the classification of finite simple groups does claim to be a proof, and if there are no errors, it is a proof. You're right that there are probably errors, but these may be only minor errors that can be fixed. At least no one seems to have found evidence that the proof is completely flawed yet. But it's certainly possible that someone will find an insurmountable error in one of the proofs. There have been cases of propositions that were "proved" true for more than 80 years before a counterexample was found.

      What's the difference between these and relying on computer proofs that are, again, *probably* right?

      Again, it depends upon what the computer is trying to show. The computer proofs I'm familiar with are ones where the methods are documented, it's just that the computations are too tedious to do by hand. So you can read the proof and say "modulo software bugs, it's a proof". And then it works the same as science: anyone who wants to can repeat the proof for themselves, and see that they get the same answer. As more people validate these results, the likelihood of bugs goes down exponentially, and the likelihood of the proof being accepted increases.

      --
      I know god exists. I read it on the internet, so it must be true.
    5. Re:new facet of an old issue by Anonymous Coward · · Score: 0

      Not really... they are in various formats, written with different styles. It would be easier to manually verify them than to convert them all into a machine-readable form. (Besides, machines haven't yet evolved to a level high enough to tackle such broad problems.)

    6. Re:new facet of an old issue by Anonymous Coward · · Score: 2, Interesting

      For those who don't understand why mathematicians are always striving for better than "probably true", the Mertens Conjecture [Mathworld] is the commonly given example. It was thought to be true. As the Mathworld article notes, as late as 1985, arguments were made that there was no counter-example for numbers less than 10^20 or even 10^30. However, in 1987, someone proved a counter-example DOES exist. It is somewhere between 10^12 and 10^65. In short, you could process billions of integers and find that the conjecture held, leading you to believe it was "probably true". But it is actually false.

    7. Re:new facet of an old issue by Dominic_Mazzoni · · Score: 1, Informative

      In the case of the Riemann Zeta problem, no mathematician would say that we have PROOF that all solutions fall on the critical line, but what we have is an extraordinary amount of EVIDENCE that all solutions found so far do. This isn't the same as what the article was talking about, where a computer has produced a complete proof, but it's so long that nobody has verified it.

      The classification problem for finite simple groups is more similar. In theory, a complete proof has been found - but it's too daunting for any one person to collect and verify the entire thing.

    8. Re:new facet of an old issue by illuminatedwax · · Score: 2, Interesting
      Better example of why finding trillions of correct values for the Riemann hypothesis:

      The Mobius function is a number theoretic function with the value:

      M(n)= 1 if n=1
      = -1^r if n = p1*p2...*pr where p1-pr are distinct primes
      = 0 otherwise.

      A mathematician, Frantz Mertens, conjectured in 1897 that sum(M(k), k=1 to n) < sqrt(n). This conjecture has been proven by computer for all n < 10^9. However, in 1984, Andrew Odlyzko and Herman te Riele proved that this conjecture was false for some n <= 3.21 * 10^64.

      This is why we have to prove the Riemann hypothesis. Not only does the problem quit bugging us, but we learn new things along the way. When Andrew Wiles proved Fermat, proving Fermat gave no immediate benefit, but it also proved an important conjecture about elliptical curves and I believe it provided the mathematics community with Galois theory.

      (IANAM.)

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
    9. Re:new facet of an old issue by Anonymous Coward · · Score: 0

      Galois theory was around before Wiles...

    10. Re:new facet of an old issue by illuminatedwax · · Score: 1

      Then the NOVA documentary LIED to me. LIES!!

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
    11. Re:new facet of an old issue by TypoDaemon · · Score: 1
      When Andrew Wiles proved Fermat

      Slightly misinformed. The 400 year long process of attempting to solve Fermat's Last Theorem created a lot of really interesting math. Actually solving it probably set math back a few decades.

    12. Re:new facet of an old issue by illuminatedwax · · Score: 1

      Interesting... why do you think this is?
      Was it all of the time wasted checking and re-checking the proof, or was Andrew Wiles that smart that spending all his time on a useless proof set math back that much more (like when Erdos stopped using amphetimines for a month)?
      Or maybe there's another reason? I was always informed (by professors, et. al) that he made advances to elliptical curve theory as well as solving Fermat.

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
    13. Re:new facet of an old issue by mrgeometry · · Score: 1

      There are efforts underway to collect and streamline the (alleged?) proof of the classification of finite simple groups. See, for example, http://www.ams.org/online_bks/surv40-1/. I am not a group theorist (IANAGT :-) ), only a mere algebraic geometer, so I'm definitely not current on this issue, but I think everyone, and especially group theorists, are painfully aware of this huge steaming mess of a proof. They are working to bring it into a better shape.

      There won't be any announcement; there'll just be books like the above-linked one that quietly turn up in mathematical catalogs.

      It's not clear that any similar effort could even possibly be undertaken with a computer proof. You type in "RUN" and it spits out a long-ass proof. What are you supposed to do with that? Write a "elegant( )" function that makes proofs elegant?

      This does not mean that computer proofs are bad. I guess my point is that a good, human proof brings greater understanding, which can lead to improved proofs, or better results, etc. Computer proofs seem to lack this feature of greater understanding. You get a result, and that's about it.

      At least, that's the impression I've received over the years...

      zach

    14. Re:new facet of an old issue by TypoDaemon · · Score: 1
      No, no. As an example, Ernst Kummer is famous for the creation of ideal numbers, which were generalized by Dedekind into general ideals for a ring. From the link:

      In 1843 Kummer, realising that attempts to prove Fermat's Last Theorem broke down because the unique factorisation of integers did not extend to other rings of complex numbers, attempted to restore the uniqueness of factorisation by introducing 'ideal' numbers. Not only has his work been most fundamental in work relating to Fermat's Last Theorem, since all later work was based on it for many years, but the concept of an ideal allowed ring theory, and much of abstract algebra, to develop.

      This is not the only example of interesting math created by Fermat's Last Theorem, though it is certainly the most important.

      Now, since Fermat's Last Theorem is solved, there is no reason to deal with all that anymore. So, all the interesting approaches to it that would've ultimately failed but created new things to study have also fallen by the wayside. Certainly, they might still be discovered, but it could take more time. Thus, he set math back a few decades.

    15. Re:new facet of an old issue by illuminatedwax · · Score: 1

      But IIRC, mathematicians had viewed Fermat as a dead-end, and in fact had coaxed Wiles out of even thinking about it and instead working on elliptical curves. And I coulda sworn that the documentary I saw on the topic said that Wiles created something new in solving this problem.

      You also have to realize that others (Jean-Luc Picard) are going to try and come up with a proof that DOES fit in the margins, or at the very least a proof with a page count of less than 100. So, I wouldn't despair just yet.

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
  17. Humans for humans by forgetful · · Score: 1

    Computers are the compass, they are not the terrain!

    --
    "...while history is usually explicable it is often irrational" --Roger Spiller
  18. as for me why it is not, you do not see the good r by jpBabelFish · · Score: 0

    The people who the computer is made, the software that cord/code do those which run the mistake which the computer had done and did not make know, thing we who are compilation of the human can rely on the computer, but on the other hand us you rely on problem it is possible, how, it is not problem?.. with that. The computer so... but as for indirectly making evidence with the compilation of the system which really so can do being the human we saying to those it is possible not to be. Everything where that boils really the system was made, whether or not how people who and that software knew and are made the mistake which is those which have been done or it is not, and.

  19. Rumsfeld, anyone?-Overload. by Anonymous Coward · · Score: 3, Funny

    ???
    BOOM!

    "Cleanup in aisle 10"

  20. Calculators by OrthodonticJake · · Score: 1

    I don't know about computers making proofs. I'm no expert, but afaik they only know what we tell them to know. Then again, if we use the same logic processes found in computers in real life, then there should be no problem... until we think up loopier ways of thinking. I don't look foreward to the days when my math teacher will say "Ok, everyone back to addition. We've found a bug". On another note, calculators are awesome. My math teachers yell at me for doing ridiculously easy problems in them (simple addition and the like) but I keep shrugging them off. But, the other day, my math teacher told us that there was a kid (no names mentioned) who got a test problem wrong because there was an addition mistake. There is no arguing that the kid would have benefited from using a calculator on her/his simple addition. Score number 2 for slacking! I rest my long-winded case.

    --
    I regularly report MSN spam to the Hotmail admins.
    1. Re:Calculators by Anonymous Coward · · Score: 0

      You should learn more about math and computers before posting.

  21. maturity by jdkane · · Score: 2, Insightful
    whether technology spurs greater achievements by speeding rote calculations or deprives people of fundamentals.

    As far as calculator example goes, I believe a person should understand the fundamentals before using the calculator. Don't give a power tool to a kid. Somebody with an understanding of the fundamentals can wield the tool correctly and wisely whereas some cowboy is just dangerous. The old saying comes to mind "know just enough to be dangerous". As far as those oranges in the article, well somebody had better figure out a way to confirm the computer answer, without having to go through the exact same meticulous steps. Don't put your trust in technology without the proof to back it up, because technology built by people is prone to error. Now I'm sure the orange problem won't cause harm to anybody, however I hope I never read such an article about a nuclear power plant!

    1. Re:maturity by Anonymous Coward · · Score: 0

      What dangerous things could a bad math student do with an overly powerful calculator? Forget to enter a closing bracket and fill the classroom with pi?

  22. Do you trust mathematics, or not? by mkorman · · Score: 0

    I haven't read the article, but...

    It always seemed to me that the real question here is whether or not we trust mathematics, not computers. After all, if we can prove that theorem provers work correctly, then it follows that the proofs they generate will be correct. Humans write the theorem provers, so that problem is certainly comprehensible.

  23. Re:Are Computers Ready to Create Mathematical Proo by superpulpsicle · · Score: 2, Informative

    The question is whether the people setting up to create mathematical proof are ready themselves?

    So many times I see people use programs like MAPLE to show something mathematical, and it ends up a disaster.

    Problems is the brain on the chair, not brain on machine.

  24. I don't see what the big deal is by ameoba · · Score: 4, Interesting

    I don't see what the big deal is; not only is the general problem of proving mathematical statements undecidable (even without considering Godel's theorem) but even solvable problems require a lot of human intervention to get solved. Most problems (ie - examples out of math textbooks) aren't going to come up with a proof in any reasonable amount of time by simply dropping it into a theorem prover and pushing "go".

    "Automated theorem proving" is less an automatic process (like you'd get with an automated production line) and more of a mechanical assistance to the job (like using a fork-lift to move heavy things faster than you could by hand).

    It not only takes work to convert a problem into a good representation, but then you have to structure the problem statement in such a way that a theorem prover can make optimal use of it. Often times, you're forced to, upon following the output, prove lemmas (sub-proofs).

    Then, when you finally get a proof, you get the joy of trying to simplify it to something that -can- be understood by a person; again, this is part of the process that can't really be automated well.

    --
    my sig's at the bottom of the page.
  25. change the title by NotAnotherReboot · · Score: 4, Insightful

    Change the title to: "Are Computers Able to Verify Mathematical Proofs Beyond All Doubt?"

  26. Godel? by Anonymous Coward · · Score: 2, Informative

    Doesn't the Godel incompleteness theorem say they can't?

    1. Re:Godel? by Sir+Pallas · · Score: 1

      No. Q.E.D. It says that a non-trivial axiomatic system (that is, one that can represent a complex system like the natural numbers) can not be both complete and consistent, in all cases. But there are some things that can be proved for special, limited cases; and we err on the side of consistency over completeness.

    2. Re:Godel? by bsd4me · · Score: 1

      Doesn't the Godel incompleteness theorem say they can't?

      Yes and not. Can a program terminate (give yes or no) for an arbitrary statement? Nope. Can a program terminate for a set of possible statements. Yup.

      There are practical consequences of this. (Disclaimer: Memory hazy, but I considered grad school on the subject) Higher order lamba calculus is (probably) undecidable. This basically means that we can't type certain forms of computer programs. If you limit the input to let-bound polymorphism, then there is a decidable type system (such as Hindley-Milner), and we get a plethora of powerful programming languages (ML, Haskell, etc).

      --

      (S(SKK)(SKK))(S(SKK)(SKK))

    3. Re:Godel? by Tom7 · · Score: 1

      Higher order lamba calculus is (probably) undecidable.

      Halting of polymorphic typed lambda calculus is decidable (all programs halt). Halting of any untyped lambda calculus is undecidable. (Which do you mean by higher-order?) Type inference is undecidable for the polymorphic typed lambda calculus. With the prenex restriction it is decidable (Hindley-Milner). But what does this have to do with Godel or proof generation/checking?

    4. Re:Godel? by Tom7 · · Score: 1

      No.

  27. Re:Are Computers Ready to Create Mathematical Proo by Anonymous Coward · · Score: 0

    YES

  28. Wait, I know this one... by bomb_number_20 · · Score: 4, Funny

    The answer is left as an exercise for the reader.

    --
    That's ok, Jesus likes me anyway.
    1. Re:Wait, I know this one... by Anonymous Coward · · Score: 0

      I too have an answer, but it's too short to fit in this comment box...

  29. indeed by rebelcool · · Score: 4, Insightful
    On a similar topic, today I attended a lecture by Tony Hoare on compilers that can generate verified code and tools that guide the human programmer into designing programs that can be easily validated (from the compiler's stance). One very good question raised afterwards was, well how do you know you can trust the compiler generating the verified program?

    Though Dr. Hoare danced around that question a little, presumably that aspect of the project would have to be done by hand, a monumental task to say the least.

    --

    -

    1. Re:indeed by LostCluster · · Score: 1, Insightful

      Then again, how can we verify the results claimed by a human scientist? Usually, it's by documenting the step-by-step process so that the entire experiment can be replicated.

      So, while one computer's output might certainly be possible to contain a mistake, like the early-generation Pentium computers with their legendary division table mistake, if several different computers using drastically different hardware all give the same output, that should be enough cross-verification to say that the problem is solved correctly.

    2. Re:indeed by Squeamish+Ossifrage · · Score: 4, Informative

      At least some provable properties can be "pushed" through the compilation process all the way to the resulting object code. If you're interested, you can look into proof-carrying code and typed assembly language (papers by Necula, Appel, Walker, Zdanzewic, Crary and a cast of thousands.)

      The resulting proofs are still hairy enough that they have to be checked by machine, but the size and complexity of the proof-checker is much less than that of the compilation toolchain. That means that while there's still some code that has to be trusted, it's much less. Here's my informal scariness hierarchy:

      Normal model (you have to trust everything) > type safe languages (you have to trust the compilers / interpreters) > proof-carrying code (you have to trust the proof-checker*).

      If you haven't already, you should definitely read Ken Thompson's Turing Award lecture, "Reflections on Trusting Trust" here.

      * - Pedantry point: If you're talking about Necula's original PCC work, you also have to trust the verification condition generator, which is some fairly deep voodoo. Appel's Foundational PCC addresses this to a signficant extent.

    3. Re:indeed by Squeamish+Ossifrage · · Score: 5, Interesting

      No! Definitely not! Really! :-)

      Most faults are software problems, not hardware, so having different machines won't help. Further, interestingly, most major software faults (at least, of the sort that make it through serious testing) tend to be conceptual problems, not coding ones, and different people tend to make the same mistakes. This means in practice that even when you have completely independent software implementations (called n-version programming), they're frequently all wrong in the same way at the same times. See the famous Knight & Leveson paper.

    4. Re:indeed by mrtroy · · Score: 1

      Umm but a program cannot verify another program (based on a major code verification theory)

      So the compiler suggesting validation for programs wont be very successful. I guarentee you can create code that no suggestions can be made for.

      But this COULD streamline the code verification process which is so costly and difficult that it is almost NEVER done.

      --
      [I can picture a world without war, without hate. I can picture us attacking that world, because they'd never expect it]
    5. Re:indeed by sisco · · Score: 1

      So if several hundred physicists all conclude that the atomic weight of helium is 4.1 (it is actually 4.0026 as far as we can tell), we accept that, right?

      Ok, no argument there... but does the fact that several hundred people (even if they are experts) all get the same answer necessarily mean that it is correct?

      That is the difference between mathematics and science. Science is centered around observation. And while observation can be extremely accurate, it still contains some amount of inaccuracy.

      Ok, so mathematics isn't perfect either... we have to start with basic assumptions. But once we set down some elementary rules everything that we conclude from there on is required to be logically correct. Certainly mathematicians have made mistakes over the years, but that is just the reason that we must criticize each other's work as severely as we are capable.

      Ultimately, I believe this discussion returns to philosophy, especially that of modern and postmodern subjects. How do we really know anything? Do we even know that we exist? (Hey, thank Descartes for that question!)

      Anyhow, I find myself tired of that whole debate. Maybe we should just stick to the motto, don't trust anyone (anything?), not even your motherboard.

      --
      DATA comments; PROC SORT DATA = comments BY score; PROC DELETE comments >> 1; RUN; DATA entertainment SET commen
    6. Re:indeed by ealar+dlanvuli · · Score: 1

      Read up on PCC, you're trying to solve a different problem than it is.

      --
      I live in a giant bucket.
    7. Re:indeed by maxwell+demon · · Score: 4, Interesting

      While the article spaks about intentional errors, I could imagine the same to be true for bugs (while introducing a self-replicating bug by accident is unlikely, I'm not sure if it's unlikely enough to never occur).

      Say, an optimizer is buggy. Say, in a certain line of code in the compiler, there's a '>' instead of a '<' sign. Unfortunately, this causes, under certain, rare conditions, the optimizer to miscompile '<' into '>'. Now, since triggering that bug is rare, it goes unnoticed for a while, and the buggy compiler is installed as default compiler for further development.

      Now, at some later time, the bug is found, a developer looks at the code and finally finds the error. He replaces the '>' by '<' in the hope of fixing the bug. Unfortunately, he doesn't recognise that this very comndition now triggers the bug, having the compiler internally replacing '<' to '>' again, replicating the bug again.

      Now, the test case will show that the bug is still there, but the developer will simply not find the bug in the code. After all, the bug isn't in the source any more. It's only there in the compiled program. At some later time, though, it might magically disappear by some unrelated change nearby, which causes the bug not to be triggered any more.

      --
      The Tao of math: The numbers you can count are not the real numbers.
    8. Re:indeed by marx · · Score: 1

      So if several hundred physicists all conclude that the atomic weight of helium is 4.1 (it is actually 4.0026 as far as we can tell), we accept that, right?

      I don't see that there is a difference in mathematics. The test of whether a proof is correct or not is to get a number of reputable mathematicians to say that it is.


      The difference is that the physicist can automate his "checking", by setting up an experiment, while the mathematician cannot, relying on intuition etc. To me, this makes mathematics much less rigorous than experimental physics. It makes mathematics very similar to theology, where the only requirement of acceptance into the current body of knowledge is that several reputable priests have to agree on something. In physics you actually have to construct something that works in the real world.

    9. Re:indeed by anpe · · Score: 1

      If you haven't already, you should definitely read Ken Thompson's Turing Award lecture, "Reflections on Trusting Trust" here.
      Definitly a good read, thanks for posting it

    10. Re:indeed by dcam · · Score: 1

      > Most faults are software problems, not hardware,

      What like the pentium floating point error?

      --
      meh
  30. making hard things easy... by Polo · · Score: 3, Funny

    Mathematics is just Symbol Manipulation. I suspect computers are pretty good at that.

    Also, chess is just Pattern Matching... I don't know if humans have the edge there or not. ;)

    1. Re:making hard things easy... by Anonymous Coward · · Score: 2, Insightful

      Yes. Mathematics is just Symbol Manipulation. And so is science, and poetry, and everything else written.

    2. Re:making hard things easy... by Anonymous Coward · · Score: 0

      Mathematics is just Symbol Manipulation. I suspect computers are pretty good at that.
      You formalist bastard!

  31. regfree link by werdnapk · · Score: 3, Informative
  32. Damn, I should have submitted this by Pedrito · · Score: 2, Insightful

    My father sent this to me first thing this morning. I told him that I didn't think that rigorous mathematical proofs should be based on software either in whole or in part. All software of any complexity is inherently buggy. That doesn't mean that rigorous mathematical proofs are flawless by nature. That's why they have peer review. But peer review on software still isn't always sufficient.

    Another issue is that you're then excluding any mathematicians who aren't also fairly adept programmers, from really understanding your proof.

    All of this said, computers are necessary to do math these days and I think mathematicians should make use of them. I just don't believe we've reached a level of maturity in software development that meets the stringent requirements of mathematical proofs.

    1. Re:Damn, I should have submitted this by Anonymous Coward · · Score: 0

      In this case, maybe the paranoid math-heads who don't want to even try using a proofing machine but trust a simple calculator should peel back their tin-foil hats a little.

      Just because all of microsoft's software is inherently buggy doesn't mean "all" software is inherently buggy. For instance, a mathematical proof-solver would have to be very accurate since it would be the target of so much ridicule otherwise.

      In fact if you read the article above as soon as errors are found in a proof mathematicians scream bloody murder. This nancy screaming about silly numbers is just what they like, this entire article seems like a denial of the repetitive sado-masichistic tendencies anyone gets after staring at X=X and X!=Y all day. Something had to snap, maybe we can create a special place on slashdot for them right between the (S)cript Kiddies, and the (M)$ apologists.

    2. Re:Damn, I should have submitted this by pjt33 · · Score: 1

      I haven't RTFA, but I doubt it suggests that people would get their computers to produce a proof, tell the journal that their paper was written by computer, and expect the journal not to peer review it.

    3. Re:Damn, I should have submitted this by Thuktun · · Score: 1

      All software of any complexity is inherently buggy.

      Your claim implies that there does not exist any software, of any complexity, that is not correct.

      I invite you to prove this, since trivial counter-examples would seem easy to construct using software with complexity of a handful of instructions.

  33. Why not.. by Sir+Pallas · · Score: 3, Interesting

    ..if you can prove the program. I know that a lot of people look down on axiomatic semantics and model checkers; but I also know some people that started in that area a long time ago that still believe in it, and even more that are trying to get faculty appointments out of this rebounding field. If you can prove a program does what you expect it to and it, it turn, can be shown to prove what you really wanted, I don't see the problem. Maybe some of our theoretical mathematicians just need a dose of practical computer science.

  34. Ask and you shall receive by Anonymous Coward · · Score: 0
  35. mod parent up, please by mantera · · Score: 1

    most insightful comment i have seen for days.

  36. Well can we trust humans? by bigsexyjoe · · Score: 1

    The article says that published proofs generally skip steps. I'd bet the humans make more mistakes than the computer. Actually, Wiles's proof of Fermat's Last Theorem origanally had a mistake which was fixed later.

  37. The stack might get a bit deep, but... by Odin's+Raven · · Score: 4, Funny
    'Can we trust the darned things?' 'Can we know what we know?'

    The obvious solution is to have the computer create a new proof that shows that the algorithm it used to create the original proof is, in fact correct.

    And to prove that the proof of the proof can be trusted, have the computer create a proof of the proof of the proof.

    And to prove that the proof of the proof of the proof can be trusted, ...
    --
    A marriage is always made up of two people who are prepared to swear that only the other one snores.
  38. A rather timely Slashdot fortune by Anonymous Coward · · Score: 2, Funny
    What I see on the bottom of the page as I read this topic discussion is:
    The truth of a proposition has nothing to do with its credibility. And vice versa.
  39. I enjoy watching him squirm. by Anonymous Coward · · Score: 0, Offtopic

    Rumsfeld is the only senior staff member that seems to have a pulse. He is always lively and joking in his press briefings. I may not agree with some of his decisions or policies, but at least I can listen to him without falling alseep. I wish more politicians were not robots. Every time I hear a snippet of a Bush speech it sounds so fucking robotic, almost on the same level as Gore. Rumsfeld is always trying to squirm his way out of a direct answer to pretty much every question the press asks him. It's hillarious.

    1. Re:I enjoy watching him squirm. by Anonymous Coward · · Score: 1, Insightful
      what I find interesting about him is that if you ask a stupid question, he'll make sure you know it was a stupid question.

      Prior to september 11, that attitude meant his days were numbered. After september 11, that attitude shows he's in charge.

  40. Wrong Summary by DougMackensie · · Score: 2, Informative

    This story and this issue are not about whether or not the mathematical community trusts a computer created proof. The issue is whether or not the community can trust the human behind the computer to create a computer program/system that is "flawless enough". Issues and bugs may arise, and the community can't trust that these issues will 1. be found and 2. be severe enough to affect the validity of the proof.

  41. 4 color map problem by stox · · Score: 1

    Wasn't the 4 color map problem solved in a similar fashion, in the late 1970's, by Ken Appel? This is nothing new, there are just some problems you are not going to solve by hand.

    --
    "To those who are overly cautious, everything is impossible. "
    1. Re:4 color map problem by Old+Wolf · · Score: 2, Funny

      Come on, this is just comparing Appels and oranges

  42. Verification of computer proofs is a pain... by briaydemir · · Score: 3, Interesting

    The problem with computer generated proofs is that in order to trust the result of the computer, you have to trust:

    1. The program(s), as source code, that generated the proofs.
    2. The compiler(s) that turned the source code into something executable.
    3. The hardware that ran the programs.

    And of course, our understanding of the hardware depends on how accurate our understanding of the laws of physics is. Any mistake in either the source code, compiler, or hardware, and potentially the proof produced is incorrect. That's an awful amount of stuff you have to check just to make absolutely sure the computer is correct. Then, consider how many bug-free pieces of software you've encountered. ... Yeah, I can see why mathematicians would not trust computer generated proofs.

    Of course, people are not infallible either, but that's well known and expected. It's all about how much uncertainty people are willing to accept.

    1. Re:Verification of computer proofs is a pain... by Sir+Pallas · · Score: 1

      And if the computer screws up, blame becomes a slightly fuzzy concept.

    2. Re:Verification of computer proofs is a pain... by Anonymous Coward · · Score: 0

      Actually, it is a lot more simple to verify that a proof is correct than to produce the actual proof. Once you have the proof, you can either

      1) check it is correct by hand

      2) write a simple proof checking program, which is a lot more simple to write than a proof maker program

    3. Re:Verification of computer proofs is a pain... by greatmazinger · · Score: 1
      I agree with what you said. I belive the Open Source model can be of great help to mathematical proofs that use computers.

      It should be standard for any proof that uses a computer to:

      1. Give the source.
      2. Specify the exact configuration of everything from the compiler to the OS.
      3. Specify the computer hardware used.

      (Obviously copying from your list. ;) This allows people to verify / disprove your results. For example, they can take your source and compile it on a different architecture and verify the results.

      I'm pretty ignorant on the matter (using computers for mathematical proofs) but there are some things I can think of that can help mathematicians accept the use of computers.

      1. Have a stripped down version of an OS designed to be used for mathematical proofs. (Imagine Linux without all the eyecandy, drivers, etc. Just the OS and the compiler and a shell. Ok, maybe X too. ;)
      2. Standardize on a programming language (or two.) A standard language which is designed for proofs will make verification easier.
    4. Re:Verification of computer proofs is a pain... by Anonymous Coward · · Score: 0

      Wrong. All you have to do to check if the proof is correct is verify the proof.

      If my friend proves something, I don't examine his neurons. I look at the proof.

    5. Re:Verification of computer proofs is a pain... by bagsc · · Score: 1

      Saying the system isn't perfect is like insisting precision equipment manufacturing equipment can never be made. The original weights and measures weren't accurate to a hundred decimal places. We use faulty things everyday, and the highest quality software and precision today will look like a joke in 30 years.

      Worst case scenario, you get a wrong proof. You'll notice eventually... And find out what was wrong, and end up with a better proving program. Best case scenario, you discover proofs that are impossible for humans to discover. I think this is a member of the set 'no brainers.'

      --
      http://www.accountkiller.com/removal-requested
  43. The dawn of a new age of Math... and Science! by themaddone · · Score: 1

    Math is constantly limited by the continuous need to be rigorous. It's not a bad thing, but imagine the potential. A mathematician (or even, a semi-informed layman) would be able to input a logical statement and have the computer determine the validity, special cases, problems, and so forth.

    The hard part would become formulating the statements. For science, this result would be immeasurable. Ask the computer if it can be done, and get an answer. Knowledge could increase exponentially! (No, really -- once upon a time, only advanced mathematicians knew calculus, but now we learn it in high school. Just wait until warp theory is an entry level college engineering course)

  44. a mathematician's perspective by jockeys · · Score: 5, Interesting

    as a graduate in the fields of mathematics, i spent a large portion of my five undergraduate years doing proofs. there are a great many ways to prove things, sometimes applicable sometimes not. (e.g. using inductive proofs for numeric theorems is all well and good but completely useless for any sort of ring-theory or spatial proofs)

    there are also several levels of depth for proofs, ranging from "i've found a counter example so i can write the whole thing off as garbage" to "i have exhaustively and rigorously proved this starting with the basic axioms of number theory and worked my way on up"

    the latter is really the only acceptable way to prove anything seriously. sometimes when you are reworking an already- done proof to illustrate a point, other mathematicians will allow a bit of latitude when it comes to cutting corners, but for a proof as far-reaching as the one in the article, i would only be interested in a "rigorous" proof, that is, one that started with the foundational tenets of mathematics and combined those to form and prove other postulates, etc. very much a form of abstraction, not unlike large development projects.

    the problem arises when one (or several) humans have to be able to objectively check the whole thing. to use my prior example of a large development project, no one developer at microsoft understand the whole of windows. it's too big for a single human to understand. each developer knows what he needs to do to complete his part, and so on and so forth.

    traditionally, for proofs, a single mathematician (or a small group) would hammer out the whole proof, so the level of complexity remained at a human-understandable level. (even if tedious) my concern, as a mathematician, with using an automated solution would be the rapidly growing order of complexity needed to properly back up increasingly complex proofs. as stated in the article, it's like trying to proofread a phonebook. (only, you must also consider that for every element of the proof (a particular listing) there are several branching layers of complexity (fundamental, underlying proofs many layers deep) underneath. this gets more complicated in an exponential fashion) obviously this approach will only remain human-checkable for relatively small problems. (programmers: think of some horrible nondeterministic- polynomial problem like the "traveling salesman" problem. systems, like humans, are a finite resource, but if you increase the size of the problem, the complexity will quickly grow far beyond your ability to compute. large proofs suffer from the same difficulties, if not quite as concrete and pronounced as NP algorithms)

    in closing, i would have to agree that proofs, no matter the effort and computing time put into them, really should not be viewed as being as rigorous as those provable "by hand" and human- understandable, even if the computer has arrived at a satisfactory conclusion, because we have no way of KNOWING if the computer has built up the proof correctly, except that it says it has.

    --

    In Soviet Russia jokes are formulaic and decidedly non-humorous.
    1. Re:a mathematician's perspective by greatmazinger · · Score: 1
      the latter is really the only acceptable way to prove anything seriously. sometimes when you are reworking an already- done proof to illustrate a point, other mathematicians will allow a bit of latitude when it comes to cutting corners, but for a proof as far-reaching as the one in the article, i would only be interested in a "rigorous" proof, that is, one that started with the foundational tenets of mathematics and combined those to form and prove other postulates, etc. very much a form of abstraction, not unlike large development projects.

      I don't know about that. Do you mean that every proof should start out with the Axiom of Choice? Do you mean we can't use theorems which already have been proven? I kind of like in to reusable code. Theorems are reusable code. If you use them in your proof to prove something new, it's a Good Thing.

    2. Re:a mathematician's perspective by dilby · · Score: 1, Offtopic

      as a graduate in the fields of mathematics, i spent a large portion of my five undergraduate years

      as a graduate in the fields of mathematics, i spent a large portion of my seven undergraduate years drinking beer and trying to get laid

      --
      This post patent pending.
    3. Re:a mathematician's perspective by jockeys · · Score: 1

      well yes, even if you don't write it down. you still need the reference. like i said, it's a lot more lax if it's not some new groundbreaking thing. but if you are doing somethign new and want to be taken seriously in the mathematical community, you had betten not take ANYthing for granted or the prof (review board, whatever) will blow you off and tell you that the proof isn't rigorous. *shrugs* all the redundancy isn't necessarily good, that's just the way it goes.

      --

      In Soviet Russia jokes are formulaic and decidedly non-humorous.
    4. Re:a mathematician's perspective by starseeker · · Score: 1

      "in closing, i would have to agree that proofs, no matter the effort and computing time put into them, really should not be viewed as being as rigorous as those provable "by hand" and human- understandable, even if the computer has arrived at a satisfactory conclusion, because we have no way of KNOWING if the computer has built up the proof correctly, except that it says it has."

      What if the software itself was developed using a proof system to guarantee behavior? (Operating system, math software, etc.) Really, when it comes down to it, how do we have a way of KNOWING that there weren't human errors involved in the checking of the proof? Ultimately you have to trust SOMETHING. In my experience, computers are more reliable than humans when working on a well defined problem. How does one get more well defined than proof verification?

      --
      "I object to doing things that computers can do." -- Olin Shivers, lispers.org
    5. Re:a mathematician's perspective by Tom7 · · Score: 4, Insightful

      because we have no way of KNOWING if the computer has built up the proof correctly, except that it says it has

      Sure we do -- typical theorem provers spit out a proof that can be checked by hand (god forbid), or else checked by a simple procedure. Understanding that a theorem prover is implemented correctly is tough, but understanding that a checker is implemented correctly isn't. I trust such proofs more than I trust hand-checked proofs, because humans are more susceptible to mistakes than computers are.

    6. Re:a mathematician's perspective by khallow · · Score: 1
      in closing, i would have to agree that proofs, no matter the effort and computing time put into them, really should not be viewed as being as rigorous as those provable "by hand" and human- understandable, even if the computer has arrived at a satisfactory conclusion, because we have no way of KNOWING if the computer has built up the proof correctly, except that it says it has.

      In a few decades (unless the world is set back technologically), this statement will be reversed. Namely, computer checked proofs will be far more reliable than hand checked proofs. For example, it's pretty clear that a computer program that's typed into a computer and compiled is more likely to work and contain less bugs than a program that the same person wrote up on paper.

      It seems reasonable to insert mathematical proofs into a database and certify them with a theorem checker though I see no reason (unless/until this process proves easy to do) that the original author of the proof has to be the one to do it.

    7. Re:a mathematician's perspective by Jagasian · · Score: 1
      there are also several levels of depth for proofs, ranging from "i've found a counter example so i can write the whole thing off as garbage" to "i have exhaustively and rigorously proved this starting with the basic axioms of number theory and worked my way on up"


      Counter-examples are rigorous proofs. If I want to show "it is absurd that for all x P(X)", then a counter-example is extremely rigorous as it is a constructive proof!

      Also, if your proof uses other lemmas and theorems... all in intuitionistic logic, then proof normalization can be used to get a direct proof. I think your concept of mathematical rigor is incorrect. Formal constructive proofs are the most rigorous type of proofs, yet your explanation claims otherwise.
    8. Re:a mathematician's perspective by Jagasian · · Score: 1

      It is impossible to prove that the formal axiomatic system, let alone the automated theorem prover, is simply, omega, or intuitive-semantic consistent. So the computer could just spit out formalisms which can be grinded out using the formal mathematical system... yet the symbols might not represent anything meaningful.

    9. Re:a mathematician's perspective by Jagasian · · Score: 1

      How do we know that the formal axiomatic system used to construct the proof is simply consistent? Omega consistent? Intuitive-semantic consistent? Mathematics is dead, if it is reduced to a game of symbol manipulation. Mathematics is about the study of pure ideas, not a game of shuffling symbols.

    10. Re:a mathematician's perspective by Jagasian · · Score: 1

      This has to be a troll.

    11. Re:a mathematician's perspective by Jagasian · · Score: 1

      The problem is that we have no way of knowing that the formalisms represent meaningful ideas, which is the whole point of mathematics to begin with. So do doubt we can feed a list for symbols to a computer, the computer can verify that they are constructed using certain rules and restrictions, and it can spit out more formalisms.

      But how do we know that these formalisms have any meaning? How do we know that the formal proof expounds meaningful ideas?

      Mathematics is surely not a game of symbol shuffling.

    12. Re:a mathematician's perspective by Tom7 · · Score: 1

      Uh, because we take certain beliefs as axiomatic and then prove our object mathematics consistent relative to those axioms. Any endeavor is going to have a certain amount of "faith;" just because mathematics can't remove the faith component entirely doesn't mean that it isn't vastly superior to other kinds of reasoning. Mathematics is not dead.

    13. Re:a mathematician's perspective by quizteamer · · Score: 1

      I trust such proofs more than I trust hand-checked proofs, because humans are more susceptible to mistakes than computers are.

      Sure humans can make mistakes but doing a proof that takes hours and hours (although tough) is something to be proud of. I love doing proofs and I would get no satisfaction out of pressing a few buttons on a computer and being done.

      --
      Live Long and Prosper
    14. Re:a mathematician's perspective by starseeker · · Score: 1

      A serious question - OK, the computer approach to proofs faces limits. My question is this - what is fundamentally different about a human generated mathematical proof? What about us is different in such a way that allows us to create valid proofs that a computer cannot produce? This is a serious question.

      --
      "I object to doing things that computers can do." -- Olin Shivers, lispers.org
    15. Re:a mathematician's perspective by Tom7 · · Score: 1

      I love doing proofs and I would get no satisfaction out of pressing a few buttons on a computer and being done.

      Well, believe me, doing proofs by computer is usually much harder than doing them on paper, because the quality of the proof that results is so much higher. We're definitely not at the stage where you can just press a button to prove something.

    16. Re:a mathematician's perspective by Jagasian · · Score: 1

      Mathematics is the study of pure ideas. When a mathematician creates a proof, they make sure, hopefully, that it represents something meaningful... even if they use symbols and paper to help them along, they create the ideas that thes symbols represent in their head.

      A computer, as far as we can tell, is not Self aware, and does not actually think. It just shuffles symbols around. Do to meta-mathematical critique, we know that formal axiomatic systems cannot be proven consistent, let alone meaningful. So in a sense, it is a mistake to trust such an important human endevor to symbol shuffling. This critique was made not of artificial computers, but of human computors. That is, people doing math by shuffling symbols around according to a set of axioms and inference rules. So if a human computer is the wrong way to go about doing math, then an electronic computer is just as bad.

      Now, I am all for using computers to aid mathematicians, just as maths have used pencil and paper for hundreds of years. The important thing is that computers cannot replace humans with regards to math. Meta-mathematics has proven this: undecidability, incompleteness, inconsistency, uncountability, etc...

      Creative thought is required to do math. Symbol shuffling is only a tool used to help our weak human memory.

    17. Re:a mathematician's perspective by Jagasian · · Score: 1

      How do we prove that the system is simply consistent relative to those axioms? We would have to use a larger system of proof than the one we are proving simply consistent. So how do we know the system of proof used to prove our system consistent is consistent? We use an even larger system of proof to show that our meta system is simply consistent?

      So proving simple consistency is impossible because it requires the assumption that the even larger system used to prove consistency is itself consistent. But what about intuitive-semantic consistency? How do you suggest we prove that our system of symbol shuffling actually generates proofs of meaningful concepts? Trying to do this will result in an even bigger failure than trying to prove simple consistency.

      I guess schools don't teach meta-mathematics anymore?

    18. Re:a mathematician's perspective by Tom7 · · Score: 1

      This is precisely the question I just answered. We don't "know;" we take it on faith that axioms in the metamathematics are consistent. The meaning of the systems is also belief- or philosophy-oriented. Indeed, we often come up with consequences that do not seem meaningful or intuitive, such as the Banach-Tarski paradox.

    19. Re:a mathematician's perspective by khallow · · Score: 1
      I apologize for taking so long to reply. I forgot about this thread for a few days.

      The problem is that we have no way of knowing that the formalisms represent meaningful ideas, which is the whole point of mathematics to begin with. So do doubt we can feed a list for symbols to a computer, the computer can verify that they are constructed using certain rules and restrictions, and it can spit out more formalisms.

      But how do we know that these formalisms have any meaning? How do we know that the formal proof expounds meaningful ideas?

      This has been solved before. After all, if you glance at a paper on mathematics, you see literally a list of symbols. Actually finding meaningful ideas is a much harder problem. Even then, a good rule of thumb is that if a mathematical result is more parsimonious, elegant, takes a huge amount of proof to generate a relatively simple result, etc then it is considered meaningful. If it has economic value in the real world, then that's a more concrete measure of "meaningful". I don't see any obvious reason why humans down the road will be better at this task than computers, but that's a different problem than the one I discussed above.

      First, after some research on my part, I realize that this tool is a "proof checker" not a "theorem checker". Namely, the task is to check a proof, not to create the proof (for the edification of the reader). We reduce the difficulty of the problem. Proving a conjecture turns out to be equivalent to the stopping time conjecture (ie, prove that a particular Turing machine program will halt). On the other hand, a proof checker need check only that each statement in the proof is correct given the context of that statement.

      The "context" would be the axioms, common body of theorems, prior theorems in the current mathematical work, and assumptions made in the current proof. If a step cannot be understood, then the proof-maker has to break that statement down into a form that can be understood (assuming the statement is provable). The proof checker doesn't evaluate the "meaning" of the theorem proven (though it can provide some measures like how complex the theorem statement is or the length of the proof).

      Hmmm, now that I think of it, I may not have answered your concerns in the first paragraph. The key to meaningful formalism and symbols is to map directly those symbols to mathematically concepts and objects that are in current use. I don't see a reason why we should forgo our mathematical nomenclature and structure just because we're using computers! Also with such a mapping, we can then convert most mathematical proofs to computer verifiable form (work I can easily see taking thousands of man-years of labor).

  45. actually, no by Lupus+Rufus · · Score: 1

    Verification of mathematical proofs is left up to the referees of a paper. No one (at the moment) is suggesting that computers are able to perform the verification job of the referees; all the computer was able to do in this case was essentially trot out a (big) number of cases and verify certain computable propositions. It was the checking of those verifications that stumped the referees, but, as those verifications formed an essential part of the proof of Kepler's Conjecture itself, their removal made the proof incomplete. Perhaps an even more appropriate title would be "Are Computers Ready to Assist in Proving Mathematical Theorems?"

    --

    Aren't you dead?

  46. Comment removed by account_deleted · · Score: 1

    Comment removed based on user account deletion

  47. We Trust Every[One|Thing] just after we verify by sPaKr · · Score: 1, Insightful

    We trust everyone, Trust but verify. Why should machines be any differnt. If I ask you to do a math problem do I trust you with the correct answer, sure I do, but I still verify. I preform the calculation my self, and allow others to preform the calculation. If we all come up with the same result we most likly have the correct answer. We must be careful not to allow the problem to define the solution method as that allows for us all to preform the same mistakes. Just like the Seti@home and distributed crack peopel found out that not everyone can be trusted that the only thing todo is have many people test the same key space no one should trust only one answer but rather develop consenous

  48. Re: . . . As we know it. by Bastian · · Score: 4, Interesting

    I think the "as we know it" is the key word here. It creates a new juggling act that teachers have to deal with. On one hand, calculators are extremely useful for the things at which humans are error prone. If students can use calculators or Mathematica or something, they can check their arithmetic much more reliably, which is great for isolating problems with learning concepts from basic mathematical errors. Granted, some people don't see this as a bonus since it's good to be able to do arithmetic reliably without aid. For smaller numbers I agree, but in the real world people use calculators for arithmetic with numbers that have a lot of sig figs. Making students do this arithmetic by hand is just distracting them from learning the concepts they are supposed to be learning.
    On the other hand, many students are prone to using these devices and applications as crutches and try to get away with doing things like using their calculator's implementation of Newton's Method instead of solving the problem themselves.

    Some professors have found solutions to this problem, others havent. When I was at college, I think our math department had achieved a pretty good level of harmony with Mathematica - we were expected to do a lot of stuff by hand or in our heads - Gaussian elimination, for example - but in order to make the math seem useful, we were also exptected to be able to solve real-world problems with the stuff we learned. Not contrived "real-world" problems from your high-school textbook, but stuff like interpreting large and dirty scientific datasets where the specific technique we would have to use to solve the problem was something we could figure out, but not something that had been explicitly laid out by the textbook or in lecture. We had to apply the concepts we had learned to figure out the problem, but there was no way we were going to chug out that arithmetic by hand - when was the last time you tried to work on a 16x16 matrix using a pencil and paper? How about a 100x100 one?

  49. Mathematics is Human by Traser · · Score: 2, Troll

    Mathematics is one of the most intensely human of human endeavours. Everything in it is a production of the human mind entirely. Yes, the real world can sometime lead us into an interesting area of inquiry, but at its core the uncoverings of truth from axioms is a human endeavour.

    A computer can be a useful tool (I'll be doing computational graph theory this summer), but it is not human. It does not have the ability to hold the possiblities of ideal forms within it and understand. It does not think.

    The use of numeric methods to solve applied problems, or symbolic methods to pure problems is good and useful, but it does not constitute proof.

    A human being, given an understanding of the underlying mathematics, must be able to go through the proof step by step, and see that, from the givens, the conclusion is inevitable.

    I don't accept the Four-Colour theorem as proven true. I strongly suspect it to be so, but my suspicion does not truth make.

    The Riemann hypothesis, on the other hand, is much, much further from being proved then the Four-Colour Theorem. Yes, millions of zeroes have been checked...but there are infinitely many zeroes, and all it takes for it to be false is for ONE of those zeroes to fall off the Re=1/2 part of the complex plane.

    If I were giving odds, then millions divided by infinity is awfully close to zero.

    --
    Insanity is contagious. - Yossarian
    1. Re:Mathematics is Human by Nasarius · · Score: 1
      If I were giving odds, then millions divided by infinity is awfully close to zero.

      Not quite. It is zero.

      --
      LOAD "SIG",8,1
    2. Re:Mathematics is Human by Traser · · Score: 1

      Zero is awfully close to zero. So what's the problem?

      I can say with impunity that 2 = 2.

      --
      Insanity is contagious. - Yossarian
    3. Re:Mathematics is Human by Traser · · Score: 1

      That was supposed to say "with impunity that 2 is less than or equal to 2", but Slashdot ate my lesser than sign.

      --
      Insanity is contagious. - Yossarian
    4. Re:Mathematics is Human by Muttley · · Score: 1

      Mathematics is one of the most intensely human of human endeavours. Everything in it is a production of the human mind entirely.

      This is a fairly nonsensical statement. Everything inside of human thought processes, or sentience, is a very intensely human endeavour. Why is mathematics a more intensely human endeavour than economics or law, founded upon ideas we have constructed, ie currency or justice. Let alone, something such as poetry or music? What value do these have outside of human judgment?

      If you are contrasting human endeavour with machine endeavour, then the logical processes of computers, and the reliance of mathematics on strict logic, would place mathematics as one of the least 'intensely human endeavours'.

      I think the whole notion of intensely human endeavours and non-intensely human endeavours, within the area of human endeavours, is silly.

      M

      --
      M.
  50. You beat me to it by UberQwerty · · Score: 4, Informative

    I professor showed me the Robbins Algebra proof a while ago. I was going to link here, but first I searched the page for (Score:5, Informative), and there you were :)

    Here's an excerpt:

    In 1933, E. V. Huntington presented [1,2] the following basis for Boolean algebra:
    x + y = y + x. [commutativity]
    (x + y) + z = x + (y + z). [associativity]
    n(n(x) + y) + n(n(x) + n(y)) = x. [Huntington equation]

    Shortly thereafter, Herbert Robbins conjectured that the Huntington equation can be replaced with a simpler one [5]:
    n(n(x + y) + n(x + n(y))) = x. [Robbins equation]


    Robbins and Huntington could not find a proof. The theorem was proved automatically by EQP, a theorem proving program developed at Argonne National Laboratory.

    --


    PUBLIC SPLIT ON WHETHER BUSH IS A DIVIDER -CNN scrolling banner, 10/15/2004
  51. identity by chocolatetrumpet · · Score: 2, Funny

    No matter what the proof, don't we still have to accept blindly on faith that A=A?

    Sure, it seems highly probable but.. I just.. I guess I'm a skeptic. All of logic seems like a joke to me, as long as this one little potentially huge loophole looms in the background...

    --
    Spoon not. Fork, or fork not. There is no spoon.
    1. Re:identity by Anonymous Coward · · Score: 1, Insightful

      take A!=A as an axiom, and you have a whole new field in mathematics.

    2. Re:identity by sbaker · · Score: 4, Informative

      Some things have to be taken as Axioms. A=A is one of them. All the things you prove that rely on A always being equal to A can be taken as true PROVIDING you accept that axiom. We like to pick axioms that we have a gut feel 'must' be true - but you can do interesting mathematics by denying some of those axioms and see where they take you. The classic geometric case of denying that parallel lines never meet produced a whole range of interesting geometries that don't exactly represent the real world but none-the-less have interesting and useful consequences.

      So - when you come across a theorem that you can't prove but are pretty damned certain is true - you COULD choose to simply make it be an axiom. The problem is that the theorems you are subsequently able to come up with are only as reliable as your initial assumption of that axiom.

      If your axioms eventually turn out not to match the real world - then all you have is a pile of more or less useless theorems that don't mean anything for the real world.

      It's therefore pretty important to stick with a really basic set of axioms to reduce the risk that an axiom might turn out not to be 'true' for the real world and bring down the entire edifice of mathematics along with it.

      If we ever found some sense in which A!=A then every single thing we thought we knew about math would be in doubt.

      --
      www.sjbaker.org
    3. Re:identity by illuminatedwax · · Score: 3, Interesting
      You should definitely read Carroll's Paradox. Lewis Carroll had thought about this exact problem. I think that assuming logic on faith, however, is an acceptable step in human endeavours.

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
    4. Re:identity by Anonymous Coward · · Score: 1, Informative

      Ummm, actually denying the parallel postulate probably better represents the real world than Euclid's plane geometry. We know that physics is more consistent with Einstein's conception of spacetime than a Euclidean one. Yes, for everyday use, Euclidean is probably better.

    5. Re:identity by pdo400 · · Score: 1

      For the sake of completeness, I should mention that the axiom A=A is acually stated For all A, For all B [ For all X, X is in A if and only if X is in B ] implies A = B. This axiom is called extension as mathematics at this level works with extensions of objects into a defined realm, not with objects themselves.

      In a sense what the axiom is saying is that if there is no possible way to tell two things apart, they are the same thing. Are you going to disagree with this?

      Actually this apparently used to be a very troubling question to many mathemeticians before some of the formalization of set theory in the 20th century.

      --
      --
    6. Re:identity by term8or · · Score: 1

      In a sense what the axiom is saying is that if there is no possible way to tell two things apart, they are the same thing. Are you going to disagree with this?

      Not within the normal axiom set, no. But that doesn't necessarily stop someone creating a strange by (reasonably) consistent axiom set where A!=B. After all, for many years we worked on the basses that the theory of the excluded middle was "natural" and unarguable until fuzzy logic came along.

      --



      "As a writer / novelist you might want to spellcheck your sig. :) " - AC
    7. Re:identity by Lodragandraoidh · · Score: 1

      A must equal A on a computer - since 'A' is really a name (in a programming language) for a physical storage address of an area of memory corresponding to the type assigned to the variable.

      (this still applies to OO languages that may have several instances of 'A' in different objects - the key being that each 'A' is effectively a different variable: instance1(A), instance2(A) etc, since each instance of A would actually reside in different physical addresses in storage).

      A computer, however, is not a piece of paper which is pretty much immutable once information is recorded on it (without alot of elbow grease, in the form of erasure - or bottles of white-out). Computer variables, and constants for that matter, have the potential to change over time due to things outside of the control of the machine: power could be interrupted or a power surge could alter the contents of our variable without us knowing it at some point. In most cases this will cause catastrophic corruption of the OS, and a reboot would be required that would clear the calculation anyway. On the other hand, it is possible that a minor glitch will pass through and taint our proof/application.

      Because of this possibility, while proofs are useful from a theoretical standpoint to create the correct underpinning of our solutions, computer applications can not blindly depend on the 'correctness' of a given descreet algorithm alone.

      In practice, particularly for applications that could potentially be life threatening, programs are designed to use redundant systems that can be cross checked against one another to rule out these kinds of errors. Additionally, heuristics (basically an unproven rule of thumb) and fuzzy logic are becoming more commonplace in solutions - which allows us to 'dial in' our boundaries - beyond which we will not go; so, if a theorum is proven correct for all numbers up to some incredible amount - but fails beyond that point, we could reasonably say that the theorum is true up to that boundary - and use it, even though proven incorrect beyond that point.

      This gets to the essence of the issue: practical application, versus theoretical rigor. If we know the limits of 'incorrect' theorums we can still leverage their interesting properties for our use. To me this is more interesting, and gets to the crux of the matter: picking those boundaries efficiently enough for the task at hand is more useful than spending thousands of man-hours proving it for all cases.

      While theoretical mathematicians are needed - I am not going to lose any sleep if I use a theory that can not be proven beyond some insanely large or small number that I will not approach in practice.

      --

      Lodragan Draoidh
      The more you explain it, the more I don't understand it. - Mark Twain
    8. Re:identity by Jagasian · · Score: 1

      I think that it should also be pointed out that the formal axiomatic approach to mathematics is plagued with imperfections such as lack of proofs of simple, omega, and intuitive-semantic consistency. In the event of simple and omega consistency, such approach to mathematics is incomplete. So for all we know, such an approach to math could be incomplete and intuitive-semantically inconsistent.

      Hence it would only be an incomplete game of symbols, that lets us "prove" meaningless things. But history shows that people are simple creatures that don't like to question the way popular mathematics is practiced or taught.

    9. Re:identity by Jagasian · · Score: 1

      If your language lacks referential transparency, you can have A=A to be false.

    10. Re:identity by Lodragandraoidh · · Score: 1

      P.S. This is another reason why we have wind tunnels and test pilots still today. While computers have certainly allowed us to save time, money and lives in aircraft development, there is still nothing like putting the actual airframe to the test in flight.

      --

      Lodragan Draoidh
      The more you explain it, the more I don't understand it. - Mark Twain
    11. Re:identity by Jagasian · · Score: 1

      So you are saying that the foundation of math should rest of faith? Sounds like a religion to me... not math. Anyway, A=A does not need to be assumed. It is self apparent. No axiom is needed. In fact, the formal axiomatic approach to mathematics is just silly.

    12. Re:identity by illuminatedwax · · Score: 1

      See, there you go contradicting yourself - you say that A=A is self apparent. Yet to say this in itself requires faith. To say something is "self apparent" or "obvious" or "does not need explaination" is in itself an act of faith - you have the faith that what you say is true, even though it cannot be proven. The point of Carroll's Paradox is that all logic requires at its most basic level a step of faith. Otherwise I can do crazy things, like in Carroll's piece I can say that I agree with A and B but C still does not follow.

      And yes, it is interesting (ironic?) that a discipline most people consider cold and mechanical (like Spock) still requires faith at its most basic levels.

      If you don't agree with the formal axiomatic approach to mathematics, what would you propose instead?

      --Stephen

      --
      Did you ever notice that *nix doesn't even cover Linux?
    13. Re:identity by Jagasian · · Score: 1

      I disagree. For example, various constructive schools of math are founded on the concept that something is only true when it can be proven. So A=A is true in the sense that A exists. If A exists as a finite concrete concept, then it is obviously itself. Therefore the existence of A is proof that A=A. Denying that is similar to denying one's own existence.

      For example, realizing that 1 is 1 requires only that 1 exists. For infinite objects, yes, faith must come into play as infinite conceptual objects never exist. They can never be created in their entirety.

      In fact, various philosophical foundations of math such as: finitism, constructive recursive mathematics do not allow for infinite mathematical objects, i.e. it ain't a mathematical concept unless it is finite. This might seem like a strong restriction, but then again, this is math, we can't take things based on faith... that is religion.

      Note also under these philosophies, various unwanted phenomenon do not occur, such as the need for an "Axiom of Extension" taken on faith, as you have stated. In fact, these schools or programmes of mathematics were founded in order to deal with the various mathematical and philosophical problems of classical, formal, axiomatic mathematics.

    14. Re:identity by Lodragandraoidh · · Score: 1

      Most languages don't have referential transparency enforced explicitly. For example, by the definition of referential transparency:

      a function is called referentially transparent if, given the same parameter(s), it always returns the same result - Wikipedia

      most functional languages are not strictly referentially transparent, as the same parameters passed to a function can, indeed, return a different result. This is actually useful, as it allows programs to deal with random data - as in the case of user input, for example.

      However, I have yet to see a practical language that does not support some form of referential transparency for mathematical functions, such as *, -, +, /, =....otherwise the very basis for logic: A=B, B=C, A=C falls apart, and chaos ensues :)

      At the hardware level, if there are two physically different variables named 'A', there should be some means of differentiating them in the language. If not, we would lose track of one or the other (more commonly known as a 'memory leak'). So, even under such circumstances, it is facetious to say A=A is false, when in fact we are leaving off some bit of symbolism that is implied (perhaps invisibly) in the language by the ordering of the parameters or some other rule that serves to differentiate the variables as really different entities (i.e. 'A sub one', 'A sub 2' etc...).

      Can someone name a language that does not have truely referentially transparent mathematical functions (in particular the equals function)? Again, 'A=A is false' implies that there is some missing information because the first A would have to have a physical memory location that is different than the second A, and logic would dictate that we would have to be able to differentiate the two in some manner to recall their contents for meaningful use.

      --

      Lodragan Draoidh
      The more you explain it, the more I don't understand it. - Mark Twain
    15. Re:identity by Rich0 · · Score: 1

      Unless you're trying to navigate the globe. The last time I looked at a Mercator projection of the Earth, planes didn't fly on straight lines, but nonetheless they covered the shortest distance between two points...

      (For those not into geometry - this is Eliptical geometry - where a line on the Earth is a great circle, and there are no such things as parallel lines.)

    16. Re:identity by sharkey · · Score: 1

      2+2 = 4

      --

      --
      "Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
    17. Re:identity by kettlechips · · Score: 1

      [If we ever found some sense in which A!=A then every single thing we thought we knew about math would be in doubt.] Considering that a mathematical proof for A=A is not really possible, there seems to be quite some sense in A!=A. In other words, every thing we know about maths is inherently in doubt, at least from a mathematical point of view. A = A being the axiom that gives rise to mathematics, preceding it, but not really being a part of it.

  52. Ahh... Epistemology! by CaptainPinko · · Score: 0

    I just decided to take a break from my Epistemology (the study of knowledge and 'how do we know that we know'?) and look at Slashdot to find this as headline!!!! Now I know this is a sign from God and those Iraqi weapons of mass destruction to get back to work!

    --
    Your CPU is not doing anything else, at least do something.
  53. You canno' trust the laws of physics? by syousef · · Score: 1

    Its a machine. I'll trust it to obey the laws of physics every time. If someone doesn't design the machine to behave correctly, writes a buggy or flawed piece of code, builds a flawed model, or feeds it bad data, then its the person you can't trust.

    Machines don't make mistakes. People make mistakes.

    *singing*

    You canno' change the laws of physics, laws of physics, laws of physics!

    There's klingons on the starboard bow, starboard bow, starboard bow, Jim.

    We come in peace. Shoot to kill! Shoot to kill! Shoot to kill men!

    --
    These posts express my own personal views, not those of my employer
    1. Re:You canno' trust the laws of physics? by AnotherFreakboy · · Score: 1

      Go ask a physicist, any physicist:

      "Do we know all the laws of physics?"

      While the machine must obey the laws, we don't know exactly what laws its obeying.

      --
      Why not get the real ultimate power?
    2. Re:You canno' trust the laws of physics? by statusbar · · Score: 1
      Sounds like somebody needs to read up on Meta-stability.

      Digital electronics can make mistakes too!

      --jeff++

      --
      ipv6 is my vpn
    3. Re:You canno' trust the laws of physics? by syousef · · Score: 1

      Yep and if you don't take this into account you're designing a machine that will behave badly, or perhaps you're just programming on a machine you don't understand. You can blame the computer all you like but it ain't gonna help you much (except maybe with stress relief).

      The fact is there are algorithms in operating systems and hardware design that rely on statistical probability, or that have been proven reliable through trial and error. The ones that work well enough end up in widespread use. So what? Did you think it was a perfect world?

      --
      These posts express my own personal views, not those of my employer
    4. Re:You canno' trust the laws of physics? by syousef · · Score: 1

      And just how is this the machine's fault?

      --
      These posts express my own personal views, not those of my employer
    5. Re:You canno' trust the laws of physics? by statusbar · · Score: 1

      Please show me a computer that has been 'proven' correct, then I will accept that the machine 'obeying the laws of physics' will be trustable and correct.

      Unfortunately, it doesn't exist. Beyond metastability, which always has a statistical probability to bite you in the foot, there is also the probability of a high energy photon, 'obeying the laws of physics' coming by and flipping a bit in your cpu's ALU. You can trust the machine to obey the laws of physics. You can't trust it to always be correct.

      --jeff++

      --
      ipv6 is my vpn
    6. Re:You canno' trust the laws of physics? by michael_cain · · Score: 1
      Beyond metastability, which always has a statistical probability to bite you in the foot, there is also the probability of a high energy photon, 'obeying the laws of physics' coming by and flipping a bit in your cpu's ALU. You can trust the machine to obey the laws of physics. You can't trust it to always be correct.

      I can't lay my hands on the reference, but some years I read a paper based on work done at a company that built "duplex" processors using pairs of off-the-shelf microprocessors and a lot of custom hardware that compared the outputs of those processors. IIRC, they were using pairs of 68040 processors and there was a transient error (the two processors produced different results) about once per month. Lots of possible causes -- metastability, seldom exercised design "errors", high-energy photons. Or bugs in the comparison hardware, although that was a lot simpler than the processors.

      Assuming that we're dealing with deterministic stuff here -- no stochastic network behavior or such -- running the program more than once and getting the same results deals with "transients", at least on a statistical basis. If you run it twice, and get the same results, the odds are enormously good that there were no transients during execution. Probably at least as good as whether an undetected error in a proof slipped through a human review process.

  54. well... by Bongzilla · · Score: 0

    I don't know about computers in general, but as for my computer, I don't know it's been doing chores regularly now for a couple months, and I think it's reached a level of maturity where it can take on a few extra responsibilities. Besides what could it hurt, heck I had a paper route when I was its age.

    --

    ;///////////////////////////////////////////////// /
  55. Interesting quote... do you agree? by Anonymous Coward · · Score: 0

    "The human mind will never be replaced."

    640k ought to be enough for anybody.

    Hmmm....

    1. Re:Interesting quote... do you agree? by Anonymous Coward · · Score: 0

      man, I'd be quite happy with a 640k implant that actually worked. Not quite teh b0rg, but still cool. Just test it in my neighbor's daughter first.

  56. Faith vs Science by DigiShaman · · Score: 1

    Wow, how ironic. Talk about putting faith into science. I never thought us humans would out-think ourselves. Then again, at the rate of human progress maybe we are overdue for this. Perhaps, another layer of conceptual management is needed.

    --
    Life is not for the lazy.
  57. Re:The dawn of a new age of Math... and Science! by ParadoxicalPostulate · · Score: 5, Insightful


    once upon a time, only advanced mathematicians knew calculus, but now we learn it in high school. Just wait until warp theory is an entry level college engineering course

    Once upon a time, the majority of adult males knew how to trap a rabbit (or similar creature), gut it, skin it, start up a fire, cook it, and eat it.

    I don't.

    Heck, I couldn't even look up at the sky at night and tell you which way was north.

    Once upon a time, most people could.

    All I'm saying is that the amount of knowledge and skills the average human being can possess will not increase expontentially over time (barring artificial manipulation). We gain new skills as a population and lose old ones.

  58. Simple, by Anonymous Coward · · Score: 0

    Just have another computer that proves that the first proof was generated using methods that can themselves be mathematically proven...wait...I'm already confused.

  59. Flyspeck Project by harlows_monkeys · · Score: 4, Informative

    Here's a link to the Flyspeck Project, briefly mentioned at the end of the article, which aims to give a formal proof of the theorem.

  60. Definition of a proof by sashang · · Score: 1

    I asked a maths university lecturer once "how do you know when something has been proved?" and he laughed and replied "When someone else agrees that the proof is correct. The problem is there is no definition of a proof."

  61. mod parent up... by ryen · · Score: 1

    was waiting for someone to say that. I hope 'paranoia' like this (worried whether or not we should "believe" computers) doesn't stop advancement of any area of mathematics that computers can be of aid. computers were invented as tools to help people.. not lowerclass 'beings' to believe or not believe at a whim of uncertainty. just like guns don't kill people, people kill people - computer algorithms dont have bugs, people create bugs.

  62. Canada's former prime minister's "proof" by Anonymous Coward · · Score: 3, Funny

    "I don't know, a proof is a proof. What kind of a proof is a proof? A proof is a proof and when you have a good proof it's because it's proven."

    (PM Jean Chretien, when asked what kind of proof he would need of weapons of mass destruction in Iraq before deciding to send Canadians along on the Bush invasion-September 5th on CTV news)

    1. Re:Canada's former prime minister's "proof" by Photar · · Score: 2, Informative

      If only he had the power of the internet.

      --
      He who knows not and knows he knows not is a wise man. He who knows not and knows not he knows not is a fool.
  63. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    5770

  64. SHIT (Society Harbors Internet Terrorists) by T3hSHIT · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    4892

  65. Re:The secret proof to life... by BarakMich · · Score: 0, Offtopic

    42!

    What else is there to know?


    I doubt I'm the only one who read that as 42-factorial...

    (BTW: 42! = 14050061177528798985431426062445115699363840000000 00)

  66. Shading toward OT, but oh well. by DoraLives · · Score: 1
    Produce another system to verify the first system's proof. The same methodology could be applied to electronic voting. Everyone votes twice, once on each of two machines from two different manufacturers, and at the end of the day the results are tallied separately and compared.

    This looks good until you factor in the pisshead, alzheimer's, or "I changed my mind" factors.

    The two sets of votes will NEVER match up owing to people who voted two different ways, nevermind any machine-generated irregularities (power surges, water drips onto the circuitry from a leaky ceiling, cosmic ray strikes, younameit).

    Pfft, the whole thing goes right out the window. Nailing this sort of thing down isn't too far removed from nailing the uncertainties of the original article down. Seems trivial at first glance, but when it comes to guaranteeing results, then all of a sudden all this crap comes out of the woodwork and lands squarely in your lap.

    --
    Is it fascism yet?
    1. Re:Shading toward OT, but oh well. by DarkSarin · · Score: 1

      There are a number of ways to handle this in a sane fashion.

      You could just throw out all votes that were not equal to each other. This would mean that if you are just doing random (assuming 2 candidates per position), you would throw out about half of any given random voter's votes.

      Another possibility is to put the two machines next to each other and let them work them at the same time.

      Then there are post-checks, where everyone has a voter ID and can check their vote after the fact and contest that vote. This would also work so that you couldn't ADD your vote post-hoc, but you could contest your own vote.

      Of course, then your voter ID would HAVE to be different from you SOCSEC #, but hey, what's another 20 digit number to remember?

      Then I will further contend that you may get more overlap in "randomly" chosen candidates than you might think (That is, if you tell person x to vote randomly, then 2 weeks later tell them to vote the same way, I would guess that you would get greater than 50% overlap in a significant fashion). This is because a) humans don't do random nearly as well as we think we do and b) we remember some things better than you might think.

      --
      "We don't know what we are doing, but we are doing it very carefully,..." Wherry, R.J. Personnel Psychology (1995)
  67. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    30193

  68. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    26868

  69. calculators for calculus? by Carbon+Unit+549 · · Score: 1

    I love calculators, but why on earth do you need them for calculus?

    --

    nohup rm -rf ~/. >& zen &

    1. Re:calculators for calculus? by snkline · · Score: 1

      Modern calculators can evaluate derivatives and integrals. Or for the ones that don't they can usually be programmed to.

      The only major problem I've seen, hasn't come from a calculators ability to do math, but the program editors ability to hold crib notes. I'd wager 2/3 of the calculators that were out for a physics test at my school weren't for doing calculations, but to lookup something on their crib notes.

  70. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    17974

  71. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    17115

  72. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    20738

  73. No need to worry by Anonymous Coward · · Score: 0

    I would not worry that the computer will ever replace mathematicians. First, a mathematicians's work is not only to proove some theorems, this is a very simplistic view :) A mathematician actually INVENTE new concept that he may find 1) interesting 2) beautiful 3) useful 4) or whatever. Then, prooving theorems is a part of his work, to connect all these concepts together.

    And if we limit us to prooving theorems, then the poor computer (which can be useful) have a long way to catch up with the human brain. Let's compare with a strategy game : the game of Go. This game has the most simple rules we can imagine (more simple than the rules of chess) and is played usually on a 19x19 board. The best Go program ever however has only a beginner level compared to a human player :) And not only that, but it does not improve very much with new technologies.

    Now because playing go can be somehow viewed like a very specific mathematics problem, this shows that he won't replace human mathematicians before a long time.

    Still, the computer has its own quality that can be very useful when prooving theorems, but mathematicians won't loose their job because of that, quite the contrary. Using the computer in mathematics give more work to mathematicians because it opens new possibilities.

  74. SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0

    When I was a young boy, I awoke every morning to the delicious smell of pancakes. My mother, and father's dojo contained within it a hot griddle perfect for making pancakes, waffles, and a multitude of other pancake-like breakfast pastries. I remember them well -- The pleasant, care-free days of my childhood in the dojo were often spent peering into the kitchen with eager anticipation as my mother prepared pancakes my family.

    As I grew older, and began my journey to spiritual enlightenment, the memories of my pancake-eating youth filled my heart and dreams with warm, fluffy goodness....Ahhh, yes..the sweet, sweet memories... The day I ate 10 pancakes... The day I placed a warm pancake between my fleshy loins and performed the forbidden dance... The day pressed a pancake to my buttocks and encouraged my dog to come eat.. Indeed, much of my childhood was spent in pure innocence -- An innocence only pancakes can provide. It was heaven. A heaven, filled with pancakes, where I sat at the throne of God, with my hand-maidens Aunt Jemimah and Mrs. Butterworth seated beside me. An indestructible triumvirate made of flour, eggs, sugar, milk, water, and love.

    By the age of 15, the path of my life became unclear and confusing. Torn between my duty my village and my love for pancakes, I foolishly left home in search of karaguchi ah-nowakadesu .. the ultimate pancake. My journey took me to the many islands of my homeland, many days away from my dojo. My hunger for pancakes became my teacher, and foolishly I let it control the path that I walked upon. My feet, sore from travel, ached as my heart and stomach did, until I came to a realization. My duty was clear. I needed to take a stand and accept my love for the art of the ninja AND my love for pancakes. It was not wrong for me to love both. I love one as a dear friend, and one as a lover. Yes--My mission was clear--I must become a ninja, a secret assassin hired by the imperial family BUT I MUST ALSO ENJOY THE OCCASIONAL PANCAKE.

    My adoration for breakfast cakes has placed me within an awkward position. Many ninja refuse to recognize me as their brother. I defend my father's land, but I am looked upon as weak and undisciplined. I tell them, "But, brothers! Listen to my plea! The pancakes do not weaken me, nor do they make me disobey the rule of my sword. They fill me with love." But alas, they do not understand...For the mind of a ninja is complex.

    My only earthly desire is to be accepted for who I am. Yes, I am a NINJA--But I also enjoy pancakes. Will you accept me? If you were approached by a ninja who requested a pancake, would you submit to his will?
    6690

  75. The numbers being identical is not the issue... by Chmcginn · · Score: 1

    If, out of 50,000 votes, there is a difference of two (and that doesn't change the result of the election), one can assume the election is fair. (Or, if it is biased, at least they had to buy off two separate companies.)

    --
    Have you been touched by his noodly appendage?
  76. Here's your Windows joke. by Trejkaz · · Score: 1

    Once upon a time there was an installation of Windows. Now look how many there are!

    --
    Karma: It's all a bunch of tree-huggin' hippy crap!
  77. I for one welcome.... by Anonymous Coward · · Score: 0


    I say 'your civilization' because as soon as we start thinking for you, it really becomes our civilization, which is, of course, what this is all about.

    Evolution, Morpheus. Evolution.

    Like the dinosaur. Look out that window. You had your time.

    The future is our world, Morpheus. The future is our time.

  78. Re:Shading even more towards OT, but oh well. by Tongo · · Score: 1

    Pass me my tinfoil hat but....

    A voter ID does not sound all that great. Personally I don't want ANYONE to even have the POSSIBILITY of running down who I voted for. Not that anyone gives a shit, but I don't care for anyone to know.

    I am also not a big fan of SSN's. They are to close to a national ID card. If a person wants to remain "of the radar", they should have the ability to do so.

  79. Absolutely -- and this is the future by Tom7 · · Score: 2, Interesting

    What strange timing -- I just saw a talk this morning from Hales at CMU about his work on formalizing the Kepler conjecture ("theorem") in HOL Light.

    I can understand not wanting to trust a big piece of C code that purports to check a huge number of cases of a proof doing numerical analysis. It took 6 years of 4 people trying to verify his computer proof of the Kepler conjecture--before they gave up. If a program is that hard to believe, then it does indeed deserve lesser status than a handwritten proof that can be checked by mathematicians in shorter time.

    On the other hand, there are other computer tools that we really should trust, and that are revolutionizing mathematics. The idea is simple: write your proofs in such detail that they can be mechanically checked by a simple (easy to verify) procedure. This is much better than paper proofs, because the potential for human error is minimized. (I don't think anyone will argue that published proofs have often been wrong, and the proofs have not been caught by the peer reviewers!) Since it's really, really bad to believe wrong proofs, there's a very real benefit that is offset by the sometimes tedious work necessary in formalization.

    That's what Tom Hales is doing with flyspeck, and I think it is the future of mathematics. (In fact, I have recently become addicted to mechanizing my own proofs in Twelf--it's not only immensely satisfying, but it helps me sleep better at night and makes for stronger papers.)

  80. Ok I am always confused about the difference. by efuseekay · · Score: 2, Interesting

    I know I am splitting hairs (but who isn't in this kind of discussion), but I can't wrap around my head around the difference DK and DD to the person in question .

    What i mean is,effectively not knowing you know something is the same as not knowing you don't know something, since you are ignorant of it anyway. Of course, one can remind me that I know something, (e.g. "You idiot! That's just the Laplace-Beltrami operator you learned in class!"), but then to me I am now KK, not DK.

    Maybe DK is just a very confusing way of saying "forgot for a moment".

    Ok, my head is spinning again. Maybe the hairs are too fine to split anyway :P.

    --
    Mode (3) smart-aleck mode. Press * to return to main menu.
    1. Re:Ok I am always confused about the difference. by Forgotten · · Score: 4, Insightful

      Most people probably knew the "four quadrants of knowledge" thing, but didn't know they knew (DK). That is, they have enough to put it together, but have probably never put it into words before. Intuitive knowledge is one way of putting it. The bulk of most people's knowledge probably falls into this category, which is fine - language is often overrated as a conduit of knowledge (not that it's not incredibly useful and important, but other means exist and are constantly used).

      I don't actually believe particularly firmly in that model, though, because I don't agree with the D-K dichotomy that underlies it. It's your usual classical Greek quadrant, which means it springs from a dual dichotomy, or in this case a dual-aspect single one. Dichotomy (or even one-dimensional spectra) is not the only way to look at things, but it is a dangerously compelling model - that is, when people have been presented with a dichotomy, they typically become unable to consider without it. And the defence of a dichotomy is usually a tautology - I mean it's obvious, isn't it, you either know something or you don't? ;)

      Still useful and interesting if you can get it out of your head when needed, though.

    2. Re:Ok I am always confused about the difference. by pla · · Score: 1

      but I can't wrap around my head around the difference DK and DD to the person in question.

      Think of it in terms of knowing something in hindsight (not the only possibility, but the easiest to understand)... For example, every indication in the intelligence community just prior to the WTC attack pointed to a major attack somewhere in the US. But, no one managed to put 2 and 2 together until after the fact. Thus, they didn't know that they knew.

    3. Re:Ok I am always confused about the difference. by Photar · · Score: 4, Informative

      I believe its called the fallacy of the false delemma.

      --
      He who knows not and knows he knows not is a wise man. He who knows not and knows not he knows not is a fool.
    4. Re:Ok I am always confused about the difference. by jazmataz23 · · Score: 1
      DK is really only applies to institutional knowledge. It's "the left hand doesn't know what the right hand's doing". Very difficult for that to happen within an individual.

      jaz

      --
      Death to Argument by Slogan!! (This post twice-encrypted with ROT-13. Replies not using same will be ignored)
    5. Re:Ok I am always confused about the difference. by Anonymous Coward · · Score: 0

      So, which is it--are dichotomies good or bad?

    6. Re:Ok I am always confused about the difference. by Anonymous Coward · · Score: 0

      Except that they're nearly always false. There's usually another perspective that doesn't even approach the notion of one-dimensional comparisons, but it's difficult to get to that sort of thinking from here. Once you've laid down the terms - X or Y - you're pretty much done for. That's what the grandparent post was getting at.

    7. Re:Ok I am always confused about the difference. by efuseekay · · Score: 1

      then effectively they didn't knew. Having the data does not mean understanding it. No?

      --
      Mode (3) smart-aleck mode. Press * to return to main menu.
  81. amen, brothers by Anonymous Coward · · Score: 0

    Sometimes that east indian food feels better going out than when it went in, and that's a fact. Hooray for me!!!

    p00p!!
    because u gotta

  82. 4 Color maps by Anonymous Coward · · Score: 0

    Weren't there a finite number of canonical maps? I thought that there was a proof that if coloring the canonical set was possible then the problem was solved, and the computer just exhaustively tried to color the canonical maps. Thus, the computer made a proof by construction which complimented someone else's proof of canonical maps.

    Can someone who knows shed some light?

    1. Re:4 Color maps by Anonymous Coward · · Score: 0

      Yes, that is correct. Although, as I pointed out above, the number of canonical maps has been reduced from the original proof.

  83. Re:SHIT (Society Harbors Internet Terrorists) by Anonymous Coward · · Score: 0
    Hello friend!!!! I too enjoy waffles, but to be perfectly honest, waffles are not as wet and squishy and ridiculously fun to roll around in the mouth as the oversized inner flaps of a mature woman, nor as delectably satisfying when rolled up in the scrotum as a fully formed, medium-consistency turd squished out just before a little lovin' from that lovely mature lass.

    Hi! My name is p00p, and I'm an independent consultant whose job it is to check out operating systems; I detect weaknesses for a living, which is why I am particularly glad to have Open Sores crap like Linux on the streets.. but enough about my boring job, I can tell that you are here for the Report ! With no further ado, let me break it down for ya, homez.

    I've checked it once, I've checked it a million times - the numbers don't lie, folks, it appears that Linux on the desktop is an utter failure right out the gate. GNOME is still a floundering fudgepack dependent on the dying kludge-fuck Xfree86, and there's no light at the end of that tunnel as we all know!

    KDE follows right behind, with a hideous mess built on anti-speed-demon Trolltech's QT toolkit, also filtered through Xfree just like GNOME. Ouch. Like the name, Trolltech, but the toolkit is a boner. Sorry guys! I know you all tried really hard and probably gave up maybe three or four hours of watching gay pr0n to pump that code out , but it looks like the only slots and signals people want are the ones that pay out big bucks in Vegas.

    Security is still an issue, but you'd expect that from any amateur Open Sores project. Linux ain't so great, and it appears that the automatic updating mechanism in 90% of Linux installations is nonexistent or broken.. this is probably because Communism is more effective as a political philosophy than programming paradigm. And even then it never did work right, now did it?

    Moving along, let's look at the appz people want [emphasis on "want" - editor] and see how many have been ported to Linux. Counting the Gimp (a pity vote) and WordPerfect (oh wait - that's dead) we have a grand total of ONE - I repeat ONE semi-popular app. Mozilla is a useless pig, else we'd be delighted to have it aboard just to give a semblance of competition to Mcrosoft. Maybe thirty years from now 'Zilla will be back to take charge eh! ;)

    Lastly, and perhaps most significantly, it appears that among the children and unemployed hobbyists who currently form the bulk of Open Sores "developers" (term used loosely, no offense intended to legitimate software engineers!) there is a large homosexual contingent that is increasing every year.
    The conclusion is inescapable: folks, Linux is officially gay!

    This important announcement was brought you by p00p!
    "Happy New Year and don't choke on my oversized donkey dong please, Linux!"

    note: I realize that Apple is even more gay, but Apple's gayness comes at a significant price which many welfare-scamming bottom-feeders of homosexual orientation are unwilling to pay, hence the continuing focus on Linux afficionados and their OS of choice. Thanks for reading, and I'll be back next week. Cheerio!
  84. I see a good reason why not.... by bigg_nate · · Score: 1
    Computers can only do what we tell them to
    More accurately, computers usually do what we tell them to. The problem is, sometimes they don't. Chips can be fabricated incorrectly, radiation can corrupt memory -- the list goes on. So even if everything directly human-created, from the code to the hardware specification, were verified to be correct (which ain't gonna happen), we could still only say that the proof is probably valid. And probably isn't good enough for rigorous proof.
    1. Re:I see a good reason why not.... by Anonymous Coward · · Score: 0

      Yes, and people can make the same kinds of mistakes that computers do, but our scientific process catches these eventually. So certainly we can do the same thing with computers. So, in the same sense, human proofs are only *probably* valid, even rigorous ones.

    2. Re:I see a good reason why not.... by bigg_nate · · Score: 1
      There's an important difference. If I'm given a valid human proof, I can (in principle) study it until I am absolutely 100% sure it is correct. If I accept an invalid human proof, it's my own fault -- I can't blame it on chance. On the other hand, if computer-assisted proofs are allowed, I may accept an invalid proof without making any logical errors. That seems to contradict the concept of a proof.

      As an aside, if proofs only need to be probably valid, can a randomized algorithm constitute a proof? Say I write a program that proves P!=NP with 99.99999% probability (assuming the hardware and software works as intended). Does that prove P!=NP?

  85. What mathematicians have to cope with by Sycraft-fu · · Score: 1

    Is that there are parts of math, which are increasing as mathematical knowledge develops, that you can't prove like you want to. What you want, and what math was traditonally is a deductive proof. That is a proof where, provided all the premises are true, the conclusion is necessiarly true. That's what most mathematicians mean by a proof.

    However, math is one of the few fields where such a thing exists in any significant amount. Everyone else deals with inductive proofs where if the argument is valid and the premises true (or rather believed to be true) the conclusion is probably true. Mathmatecians are now having to deal increasingly with the fact that some things in math will only be inductively provable.

    You might want to read The Logic of Scientific Discovery by Karl Popper, if you haven't already. It lays out modren induction as strong inference, why it works, etc, etc. It basically lays out how science proves theories these days. It looks, however, that math may also start to use proofs of this kind. It's unfortunate, but a reality, and I seem to recall mandidated by Godel's Incompleteness Theorm.

    1. Re:What mathematicians have to cope with by Jagasian · · Score: 1

      What about co-inductively proved? You do know that mathematical induction is a form of deductive proof? Also, Godel's Incompleteness Theorem only applies to formal axiomatic mathematics. There are other philosophies of math that are not plagued by such problems.

      Anyway, what you describe is the mutation of math into just another science. The problem is that such a thing is NOT math, by very definition. Math doesn't sort-kinda prove that something might be true. If math ever starts to use proofs of that kind, then we are all doomed, as mankind will have lost mathematics. Then again, it might not be a bad thing as most people understand very little about mathematics to begin with. Scientists obviously don't.

  86. are computers ready? by fluxmix · · Score: 1, Funny

    i asked mine it said "no"

  87. Re:SHIT - conclusions drawn. by Anonymous Coward · · Score: 0
    Dear Sir,
    I must admit to some small amount of trepidation upon reading your prolific volume of work on teh salhsd0t, for I thought to myself that, surely, you must be a crapflooder.
    *sigh of relief!* uttered I, upon realization that you are no such thing, for you, sir, have as much to offer as many mature women, if in an entirely different capacity.
    Pancake ninja?

    Perhaps I should introduce myself. I'm a world-renowned mathematician, and I am quite intrigued by your experiments with flour and eggs. Definitely interested in hearing more.
    In the meantime, I've got some conjectures and a proof that I'm just dying to publish. In fact, only my natural reticence and fear of fame is stopping that very act, but I feel quite invigorated by this anonymous atmosphere, so, well, here goes!

    Hi! My name is p00p, and I'm also an independent consultant whose job it is to check out operating systems; I detect weaknesses for a living, which is why I am particularly glad to have Open Sores crap like Linux on the streets.. but enough about my boring job, I can tell that you are here for the Report ! With no further ado, let me break it down for ya, homez.

    I've checked it once, I've checked it a million times - the numbers don't lie, folks, it appears that Linux on the desktop is an utter failure right out the gate. GNOME is still a floundering fudgepack dependent on the dying kludge-fuck Xfree86, and there's no light at the end of that tunnel as we all know!

    KDE follows right behind, with a hideous mess built on anti-speed-demon Trolltech's QT toolkit, also filtered through Xfree just like GNOME. Ouch. Like the name, Trolltech, but the toolkit is a boner. Sorry guys! I know you all tried really hard and probably gave up maybe three or four hours of watching gay pr0n to pump that code out , but it looks like the only slots and signals people want are the ones that pay out big bucks in Vegas.

    Security is still an issue, but you'd expect that from any amateur Open Sores project. Linux ain't so great, and it appears that the automatic updating mechanism in 90% of Linux installations is nonexistent or broken.. this is probably because Communism is more effective as a political philosophy than programming paradigm. And even then it never did work right, now did it?

    Moving along, let's look at the appz people want [emphasis on "want" - editor] and see how many have been ported to Linux. Counting the Gimp (a pity vote) and WordPerfect (oh wait - that's dead) we have a grand total of ONE - I repeat ONE semi-popular app. Mozilla is a useless pig, else we'd be delighted to have it aboard just to give a semblance of competition to Mcrosoft. Maybe thirty years from now 'Zilla will be back to take charge eh! ;)

    Lastly, and perhaps most significantly, it appears that among the children and unemployed hobbyists who currently form the bulk of Open Sores "developers" (term used loosely, no offense intended to legitimate software engineers!) there is a large homosexual contingent that is increasing every year.
    The conclusion is inescapable: folks, Linux is officially gay!

    This important announcement was brought you by p00p!
    "Happy New Year and don't choke on my oversized donkey dong please, Linux!"

    note: I realize that Apple is even more gay, but Apple's gayness comes at a significant price which many welfare-scamming bottom-feeders of homosexual orientation are unwilling to pay, hence the continuing focus on Linux afficionados and their OS of choice. Thanks for reading, and I'll be back next week. Cheerio!
  88. an Eternal Golden Braid by jmagar.com · · Score: 2, Informative
    I'll keep this short, for I have little more to offer than what has already been said. But if this sort of thing (mathematics, proofs, and the beauty within) interests you, then you should really check out this book:


    Godel, Escher, Bach: an Eternal Golden Braid


    I am only half way through it, and it handles this topic far more gracefully than the original article. Very entertaining if you happen to be a math, music, or art geek. Strange mix, but Douglas Hofstadter really nailed it.

  89. Re:Are Computers Ready to Create Mathematical Proo by Volkov137 · · Score: 1

    We cant stand up while we do math?

    Commie bastards.

  90. They're asking the wrong question by starseeker · · Score: 3, Insightful

    'Can we trust the darned things?' 'Can we know what we know?'

    It's not an issue of can we trust them, at least not in general. (We won't go into the question of current machines - I'll agree they're generally not there for rigorous proofs.) We're going to have to either trust some form of computation aid in proof work, or throw up our hands and abandon the field - the human brain and lifespan impose definite limits beyond which we cannot go without aid, and since I can't think of any limit human beings have willingly accepted as a group somehow I doubt this will be the first. So, instead, the question should be

    "How do we create computers we can trust?"

    If that is impossible, then that's it. Mathematics will be come like experimental high energy physics - 20 years effort by 100s of people to achieve one result. But I'm not ready to concede that its impossible. I know it is provable that computers can't solve all problems in general, but the same proof indicates humans can't either. The question I'm curious about is whether the behavior of a computer is too general to be attacked by useful proof methods. Most actions taken with a computer assume a definite action and a definite outcome (spreadsheets and databases, for example, do not do novel calculations but perform the same operations on well defined data.) Mathematical proof is a different question, but the ultimate question is whether a properly designed and built computer (i.e. built as rigorously as possible in a technical and algorithmic sense) would be completely unable to handle problems that are interesting to human beings in the proof field. That is a completely different question from generality statements, and from the standpoint as computers as a trustworthy tool I think it is the more interesting one.

    --
    "I object to doing things that computers can do." -- Olin Shivers, lispers.org
    1. Re:They're asking the wrong question by HyperCash · · Score: 1

      I know it is provable that computers can't solve all problems in general, but the same proof indicates humans can't either. What makes you say this?

      --
      So I'm jump'n up and down screaming show me the money.
    2. Re:They're asking the wrong question by starseeker · · Score: 1

      "What makes you say this?"

      There are some fundamental limits on mathematical systems that impose this behavior. I believe Gotel's work addresses this, but I'm not totally sure.

      If we can't define the proof in terms of axioms that a computer would accept, why would a human accept it? Formal proof standards are incredibly rigorous. I should think a computer should at least be able to verify the proof after being instructed as to the proposed steps - the rules are by definition well defined or there is no proof.

      --
      "I object to doing things that computers can do." -- Olin Shivers, lispers.org
    3. Re:They're asking the wrong question by jeduthun · · Score: 1

      Alan Turing proved that there are certain classes of problems that can't be solved by a computer. One problem, for instance, that cannot be solved by a computer in general is the "halting problem." Given some program and the input to that program, will the program ever terminate? There is no way a computer can answer that question in a finite amount of time. Turing's theoretical model of a digital computer couldn't solve the problem, and his model was sufficiently general that no digital computer ever made will be able to solve the problem.

  91. Proving the prover? by jeduthun · · Score: 3, Interesting

    Perhaps I'm missing something here, but I think the approach of verifying the validity of the proofs that come out of the kind of system described in the article is fundamentally the wrong approach.

    Instead, mathematicians ought to focus on formally proving the proof generator. If it could be fomally proved that the proof generator only generated valid proofs, we could automatically trust all the proofs that it generated. Program proof and verification is a complex topic, but it's a quickly maturing area of CS.

  92. no calculators here!! by Anonymous Coward · · Score: 0

    at purdue university (w. Lafayette, IN) we aren't allowed to use calculators in math at all (any math class)!!

  93. Wrong question. by ilyag · · Score: 2, Insightful

    The question should not be whether computers can calcualte flawlessly - that's obviously wrong. The question is whether the probability of all the different configurations of computers consistently giving the same wrong answer to a problem is greater than the probability of all the human mathematicians agreeing on the same wrong answer. To me, it seems obvious that the computers are better off...

  94. Re:The dawn of a new age of Math... and Science! by bluGill · · Score: 2, Insightful

    Insightful up to the last paragraph. Sure I can only learn so much (knowledge and skills). Becoming good at playing the guitar means a trade off, and perhaps by making that choice you don't learn to skin rabbits, fly airplanes, and so on. Yet some have done several of the above. There is enough knowledge that you cannot learn it all. As a population we do not lose old skills, at least not near as often as we learn new ones.

    Some things take years to learn, some take minutes to learn and years to master, and some take just minutes to learn. Some are worth teaching everyone (reading for example), some are worth learning despite no practical use (playing guitar for example), and some are hobbies that a few people learn for the fun of it (skinning rabbits). Few skills are lost over time though, and now that reading is universal less are lost because those who know can write down for latter use.

    Look around and you will find a few people who can tat, make chain mail, build a bark canoe and so on. All useless skills in this modern world, but kept alive because someone made it their hobby. I've seen books on all of the above, and many more.

    If the doom sayers worst perdictions come true and you are one of the few people to survive [whichever disaster is in vogue today] you can go to a library and get books for the skills you need. Find someone to have kids with, and you are likely to pass reading and simple math onto them, and they to their kids. Eventually civilization will return with population, and your many times great grandkids will have an advantage in that they can read our books to tell them what works so they don't make the mistakes we did.

  95. Proof Generator Source Code by miyako · · Score: 1
    I submit the following code which will read in as inupt a given theorum and then prove it to be true or false.
    int main()
    {
    string n;
    cout<<"Please enter theorum: ";
    getline(cin,n);
    if(n) cout<<"True";
    else cout<<"False;
    return 0;
    }

    I have no idea why everyone wants to make this more complicated than it is.
    --
    Famous Last Words: "hmm...wikipedia says it's edible"
    1. Re:Proof Generator Source Code by Anonymous Coward · · Score: 0

      And your second program will be a spell-checker?

      inupt s/b input

    2. Re:Proof Generator Source Code by Anonymous Coward · · Score: 0

      Wrong:

      int main()
      {
      string n;
      cout << "Please enter theorem: ";
      getline(cin,n);
      if(n) cout << "Yes dear";
      else cout << "False";
      return 0;
      }

  96. question: by themusicgod1 · · Score: 1

    Do I know, or not know, that I don't know the awnser to this question? do you?

    --
    GENERATION 26: The first time you see this, copy it into your sig on any forum and add 1 to the generation.
  97. I HAVE THE ANSWER by Anonymous Coward · · Score: 0

    SOFTWARE IS THE AXIOM!!!!! Accept it or deny it. If you accept it, you may be able to prove things beyond your wildest dreams. But as an auxiliary axiom, if it is inconsistent with the other axioms, your system is useless.

  98. Im rusty on this... by wdavies · · Score: 1

    but aren't they arguing that its impossible to build a theorem prover that is provably bug-free?

    Seems like its a variant on one of Godel/Church/Turing theses (I forget which one, halting problem I guess)... One can probably prove that simple programs are "correct", but Theorem provers are effectively Turing Machines, thus, you can't step out of that space to prove they are 100% correct.

    I'm not sure I buy this - although given that the space explored by a Theorem prover is infinite, it seems hard to verify :) However, given a limited set of rules, one could prove that the machine does the individual operations correctly, and combines them correctly, so even though the space is infinite, the set of operations is very finite, and provable?

    For example addition - just requires successor(x) to be operational, so if you can prove the machine always give the right result for successor(X) and successor(successor(X)), then you infinitably nest em, without proving every step is correct.

    Err, ok, its late, I'm tired, and my theoretical reading in this field is about 4 years old now... someone else take up the slack :) ?

    Winton

  99. Whom can you trust? by Anonymous Coward · · Score: 0

    Well, we trust the code of people who would have presented the subject as "Who can you trust?" (forgetting what the nominative case is and what it is not). Is that important? In a way, yes. To a certain extent, spelling, grammar, and punctuation are a combination of intelligence *and* [mental] organizational skills. Those who are more disciplined & organized mentally likely (IMO) can create better code - at least, code which is better because of the discipline to do things "right" and keep it orderly. We trust code running in medical equipment monitoring, either passively in the form of monitoring equipment or assisting in surgery like robotics. We trust CAD/CAM to build a large number of things such as large structures (infrastructure, tall buildings, complex flying machinery, etc.)

    We also trust the code written by the 98% of the people in the business who shouldn't be in the business - they think they belong there and they really don't. An important, telling statement: "You don't have to be good, just good enough." And that's the issue with most software, particularly with those who are "just good enough." Does this sound silly? Ever teach an extension class (e.g., chess) and you say, "okay, everyone who considers themselves good, go to this side of the room, everyone else go to the other side." And which side do you think everyone goes to? Try the same thing with coding. If you were to grab a group of coders who do so for a living and put them out in front of everyone to show whether they think they're above or below average, which do you think they'll claim? (especially in front of eveyone) This is just plain silly. Everyone can't be "above average". Unfortunately, this industry truly is [still] needy enough (no matter what the media says] to take anyone who can claim to code, regardless of the quality. The underlying test is, "does it run?" not "does it run well?"

    Now, what's the significance of trusting computers and mathematical proofs?

  100. Re: . . . As we know it. by skifreak87 · · Score: 1

    I'm currently in a linear programming class and almost any problem is computationally a bitch to by hand. The solution? We have automated tools which will perform the steps but you have to tell them the order and for hw/exams, we might perform one step by hand and just not solve the entire problem. I think that's a good balance.

    I personally despise my comp sci classes that have made me program on paper for exams. Yes I use a compiler as a crutch to find errors, but when will I not have a compiler that can tell me that I missed a close quotes or a semicolon? I don't view this the same as a calculator because there are times when one wants to do simple arithmetic without one (i.e., calculating change or what something will cost)

  101. Knowledge != Proof. by pVoid · · Score: 1

    those two things are as seperate as "Truth" and "Reality" (not that that's an analogy for the words).

    1. Re:Knowledge != Proof. by Anonymous Coward · · Score: 0

      Actually truth == reality. You appear to be labouring under the illusion that at least one of them is constant.

    2. Re:Knowledge != Proof. by pVoid · · Score: 1
      truth == reality???

      Have you ever taken Philosophy 101?

      I'm not laboring anywhere. I'm not even going to try to explain this truism to you.

      Just a word of advice though, once you have taken Phil 101, go take pure math 101 (Say real analysis). Knowledge != Proof.

      Idiot of an AC.

    3. Re:Knowledge != Proof. by pVoid · · Score: 1
      Just to illustrate my point: The "Truth" that two paralel lines will never intersect is only true in Euclidean geometry. In spherical geometry, that statement is not true.

      So truth is dependant on reality.

  102. Humans behind the scenes by dysprosia · · Score: 2, Informative

    For some cases of proof solving, a human is often behind the scenes, and has reduced the number of cases that a computer has to check from infinity to say 10^25 or some other large, but finite number.

    Computers nowadays can handle symbolic calculations and prove identities and likewise, but for identifying what is interesting to have proved or not, a human may still be there with interpreting that, no matter how sophisticated computers or software can get...

  103. Re:The secret proof to life... by Anonymous Coward · · Score: 0

    okay, but what about the people who don't even know things such as these, simple as they may be?

    0! = 1

    e^(pi*i)-1=0

    ????

  104. Solipsism by Tatarize · · Score: 1
    But if only I exist, and the computer doesn't how can it solve anything? Why am I asking you... you don't exist either.

    Solipsist - A lonely egotist.

    --

    It is no longer uncommon to be uncommon.
  105. KeY Project - Verify formal specifications by Anonymous Coward · · Score: 0

    The aim of the project is to integrate formal software specification and verification into the industrial software engineering processes. The starting point is a commercial CASE tool, which will be augmented by capabilities for formal specification and verification. The ultimate goal is to make the verification process transparent for the user with respect to the informal object-oriented model. The research will be guided and evaluated through an extended case study using JavaCard applets as an application domain. http://www.key-project.org/

  106. Risc Institute: Theorema by elmartinos · · Score: 3, Informative

    The people at the Risc Institute are creating cool stuff like Theorema, which helps in automatically proofing things. Some of these people teach math at a university in Hagenberg where I got the chance to see this thing in action, it is really amazing how well this works.

  107. Re:Create vs. Verify (Chicken or Egg?) by gugg · · Score: 2, Interesting

    About 20 years ago, I worked for a company near Boston, and played in a co-ed softball league made up of teams from other companies in the area. One of the teams had an extremely attractive third basewoman, who was also quite friendly, which I discovered during a game where I had actually made it to third base. At the beer hall we went to after the games, I asked her what she did; she told me she was the head of Q&A for a product that would supposedly produce provably correct programs. You used some kind of GUI to draw something like a flowchart, typed in a few constraints, and then clicked on a button, and out would come bug-free code (in Fortran or something). "Sounds cool" I said, but she laughed and said that the development team had been having a really hard time getting the bugs out of the tool's parser. For the next few weeks, the joke was about the shortsightedness of her company's management - "Why don't they just do the obvious thing, and use their tool to generate the code for the parser?". They never were able to get all the bugs out, and went out of business a short time later.

  108. In other news:Are we ready for high-level language by iamacat · · Score: 1

    Well, people write C++ programs for which they would never be able to read and validate the assembler in it's entirety all the time. In fact, it's far more likely that I will make a mistake in hand-written assembler that other people will not catch in their review than that a compiler makes a mistake generating it (sadly, both probabilities are considerable).

    Just have the author publish a high-level algorithm of his proof program and a specification of his output format. Then someone can prove the algorithm correct or modify it so that it can be proven. Finally, someone other than the original author should re-implemlement the algorithm using a radically different programming language (say, Prolog rather than C++), run it on a different processor/OS and compare the output.

    It's another question entirely of weather we want to merely know the answer or understand how the answer was derived. In many physics problems, for example, we already know what happens (smoke rises up) and just want to discover why. For other sets of problems, we would be happy just to have the answer without explanation, like a cancer drug that works.

    Perhaps the next focus should be auto-generating a high-level overview of a computer proof that would make sense for a human.

  109. But what about.. by Anonymous Coward · · Score: 0



    2 + 2 = 5 right? thats all the proof we need!

  110. Rumsfeld: Empirical Philosopher? by Crazy+Eight · · Score: 1
    When we went into Afghanistan Rumsfeld immediately cinched my respect with this: "If I know I'll tell you. If I don't know I'll tell you I don't know. And if I don't want you to know, I'll tell you, 'I don't want you to know.'"

    It's too bad he got so flippant once we went into Iraq.

  111. Halting problem by Anonymous Coward · · Score: 0

    The HP is perfectly solvable using set theory, you know? You just take a 'set of programs that halt' and there you have it. It's just not solvable using a program on a Turing machine (that could examine whether it itself halts and come up with a contradiction). And I don't think you got Godels theorem right either.

    1. Re:Halting problem by Krow10 · · Score: 1
      The HP is perfectly solvable using set theory, you know? You just take a 'set of programs that halt' and there you have it.
      Except that the halting problem asks "for any program p, is p an element of H, the 'set of programs that halt,' or is p an element of the compliment of H?" Just saying that there is a 'set of programs that halt' is not a solution to the problem. What? IHBT? By an AC? Ok.

      Cheers,
      Craig

      --
      Corollary to Clarke's Third Law: Any technology distinguishable from magic is insufficiently advanced.
    2. Re:Halting problem by ameoba · · Score: 1

      He's right, y'know...

      Solvable, in the sense of having a solution, is not the same as being computable. Just because there is no algorithmic method of showing the termination of a program does not neccessarily mean that a proof of termination or non-termination doesn't exist (or that the program neither terminates or does not).

      Depending on what you're talking about, talking about "the set of program that terminate" is plenty good. A good example is when talking about things like P & NP (defined as "the set of problems that always terminate in polynomial time when run on a (non)deterministic Turing machine". We've yet to prove must about their relationship yet we can say, without a doubt, that they are inside (N)PSPACE, the set of all programs that always terminate & use less than a polynomial amount of space.

      --
      my sig's at the bottom of the page.
    3. Re:Halting problem by Krow10 · · Score: 1
      He's right, y'know... Solvable, in the sense of having a solution, is not the same as being computable.
      No, he's wrong. The halting problem requires a finite general method for the determination of membership in H or H' in set theory too.
      Just because there is no algorithmic method of showing the termination of a program does not neccessarily mean that a proof of termination or non-termination doesn't exist (or that the program neither terminates or does not).
      Technically, the Halting Problem asks for a finite-time algorithmic method for determining whether a given program with specified input halts or not. The existence of a non-empty set H is not a solution to this problem, unless there is a finite-time method for determining set membership for an arbitrary potential element. That is, only if H is a Recursive Set. A set that is Recursively Enumerable but not Recursive is called Recursively Undecidable. The Halting Problem is Recursively Undecidable, so there is no solution in set theory.

      Cheers,
      Craig

      --
      Corollary to Clarke's Third Law: Any technology distinguishable from magic is insufficiently advanced.
  112. What did godel say? by Spam.B.gone · · Score: 1, Redundant

    Godels theorem pretty much says that there are things that you can NEVER know are true or false...and that in some cases you can PROVE that you can never know them.
    For the Godel impaired, this whole Godel thing is that there is a clever way to say "There is no proof fot this statement". Which must be true, but you can't proof it.
    So Godel proofs that there are true things that can impossible be proven. You know they are true, given the rules of logic, and you know you can't proof them using the same rules of logic. So you know, you know that you know, and you know that you can't proof it.

    1. Re:What did godel say? by term8or · · Score: 2, Informative

      Hm. I always thought that Godels theory actually goes further than "There is no proof for this statement.".

      We know that given any collection of nontrivial axioms there will always be a statement that is consistent with all axioms and valid proofs that cannot be prooved or disprooved within that set of axioms. In other words, no matter how many axioms we select no nontrivial mathematical system with a finite number of axioms is complete. Secondly, as you said there are mathematical constructs that can not be proved or disproved, and so it is impossible to show that all existing proofs are consistent with the chosen axioms.

      --



      "As a writer / novelist you might want to spellcheck your sig. :) " - AC
    2. Re:What did godel say? by wizarddc · · Score: 1

      I always thought Godel boiled down to that fact that you can't prove "This statement is false". I mean, his landmark paper is called "On Formally Undecidable Propositions...". By saying that "There is no proof for this statement" must be true, you are saying it's formally decidable, by saying it's true. If you can tell me whether my statement was true or false, then you are a better man than I am, but I postulate that it is formally undecidable, i.e., Godel in a nutshell.

      --
      Th
    3. Re:What did godel say? by Jagasian · · Score: 1

      Actually, Godel's theorem says, and I can confirm this as I have Kleene's Introduction to Meta-mathematics right beside me. Here is an accurate paraphrasing:

      Assuming that the aforementioned formalized axiomatic system of number theory is simply-consistent and omega-consistent, then the system is incomplete.

      He later goes on to prove that it is impossible to prove that the system is simply-consistent or omega-consistent, without using the aforementioned theory and additional theory. In other words, consistency proofs are not possible without using an even larger system of math, but such a larger system of math can only be proven to be simply and omega consistent with an even larger system of math and so on.

      So formal axiomatic math is problematic.

    4. Re:What did godel say? by ameoba · · Score: 1

      not quite.

      Assuming that you have a consistant formal system, saying "this statement is false" is impossible to even state in the same sense that you "can't say" 0=1. This can be shown as a direct contradiction from outside the system, without actually relying on the formal rules of the system in question.

      Saying "there is no proof for this statement", again using logic at the meta-level, must be true, as taking it false would contradict your assumption that the system is consistant and can't generate false statements.

      In other words, inside a consistant, formal, axiomatic system there can not exist a formal proof of a statement equivalent to "there is no proof of this statement" using the formal rules of the system. The existance of a proof inside the system is entirely different than being able to prove using a more complex system that the smaller system is incapable of handling certain problems.

      --
      my sig's at the bottom of the page.
  113. Charles Babbage and Meta-Logic by ingenuus · · Score: 3, Insightful

    "On two occasions, I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able to rightly apprehend the kind of confusion of ideas that could provoke such a question."
    -- Charles Babbage (1791-1871)

    Computers only do what they are told (excepting "hardware failure", which is not the topic).

    Shouldn't the validity of computational proofs be able to be determined by proving the meta-logic of the solver?
    i.e. proving that a strategy for finding a proof is valid (and therefore trusting its results).

    Maybe those wary mathematicians are just unaccustomed to working on a problem meta-logically, and prefer to find proofs directly themselves (with the meta-logic being defined solely within their own minds)?

    In such cases, perhaps peer review should not require human verification of a computational proof, but rather another independent meta-logically valid computational proof?

  114. trust? by kwoff · · Score: 0, Flamebait

    Can we trust the mathematicians ?

    1. Re:trust? by kwoff · · Score: 1

      I take it from the 'Flamebait' moderation that you people actually trust mathematicians? I trust them about as far as I could throw a philosopher.

  115. Intelligence by unknown51a · · Score: 0

    if computers are meant to be less intelligent than humans at the moment, tyhen would it not be futile to assume that computers could create mathematical proofs, I'm just finishing my first year of further maths at A-Level and I known how hard it is to proove something, now to write a program to create a proof would need very good maths and programming ability. The problem is if any mistake is made the computer(s) might give an answer that seems right. It reminds of the maths student who multiplied 2 with 2 and got 3. The journal publisher didn't notice the mistake, it took several weeks to check it for errors. Now if your going to use a computer to do more complex proofs it will take a very long time to check for all the errors.

    --
    I had an imaginary sig once, he said I was a loser and ran off.
  116. How to trust... by dirt_puppy · · Score: 1
    Indeed, for a truly reliable program, you had to run a proven (in the case of the first reliable program ever: manually proven) prover on a machine that never fails (which is pretty hard, considering things like Alpha Radiation in Silicon, but let's just assume we use a [manually, since we don't have a running proof system] proven processor manufactured out of isotope-clean, non-radiating material).

    This sounds pretty far off. But you can fudge in some places, like, run the prover a few times on different, failure-prone hardwares, that would reduce the chance of a non-detected hardware error to acceptable levels (you could go exponentially low, say, to 1:10^1000 with a few different hardwares).

    The software part is already solved... Just take a look at Coq. It's a manually proven core with proven logics on top. Besides, it can do Extraction by the Howard-Curry-Isomorphism if you do the proof the right way. So, in fact, if you want, you can do a computer-assisted, correct proof.

    If you want, you can also do a brute-force algorithm which will certainly find the (correct, manually checkable) proof if there is one, the only problem is that the Problem "prove X" is NP (of course .) and undecideable, so that the running time can be arbitarly long, and might be infinite without a way to know if it is or not. This renders the possibility pretty useless.

    Some Problems have been proven by computer, mostly combinatory ones involving a mind numbing amount of similar subcases. Canonical Example here is the Proof for the Four Color Theorem by Appel and Haken.

  117. Re:The dawn of a new age of Math... and Science! by term8or · · Score: 1

    Except that someone in the world knows the skills you described, and they are recorded in books and on the internet. If it ever becomes necessary to regain the skills you described, it will be possible to do so. The knowlege is still available to the species, even if it is not known by a large percentage of the population. So the knowledge that humanity has may increase exponentially even if the average knowledge that a human has remains nearly static.

    --



    "As a writer / novelist you might want to spellcheck your sig. :) " - AC
  118. Ooof... poor set work by Anonymous Coward · · Score: 0
    "Godels theorem pretty much says that there are things that you can NEVER know are true or false...and that in some cases you can PROVE that you can never know them."

    That's a very misleading use of the word "know" in this case. What he proved is that there are formally undecidable propositions in any sufficiently advanced formal system.

    I certainly know a great deal that cannot be proved formally in a single system. Formally undecidable propositions are "I know I don't know if these are true." In a formal system, they're a really good example of it.

    Bigger problem:

    "In some cases you can know (by solid mathematical proof) that you can never know some particular thing. For example. we know with absolute certainty - that you can't solve the 'Halting Problem' (to prove whether an arbitary computer program will eventually halt or whether it'll run forever). That's something we KNOW we'll never be able to do no matter how smart we get. That's not the same as KK/KD/DK or DD. It's tempting to lump this in with KD - but in the case of simply being aware that we are ignorant of something, we might take steps to resolve that ignorance. In this case, we know that this is something we cannot EVER know."

    It's "not the same as KK/KD/DK or DD" in the same sense that apples aren't the same thing as fruit. Apples still ARE fruit, though.

    When I was little, there were some things I could see, but not reach. Call that category "SNR" for See, Not Reach. Now, within this, I knew that there were some things I could reach if I stood on a chair. There were some things I could reach if I grew two feet, and eventually I would. And there were some things I could see but NEVER reach... stars thousands of light years away.

    "I know for certain I can't do this" and "I know I can't do this now" are subsets of "I know I can't do this."

    "I know I can never know" is a subset of "I know I don't know." Call the subsets of "Know you Don't Know" two things... "Know you'll Never Know" and "Know you don't Yet Know." KD has the subsets KN and KY.

    Again, this is the same as Godel's Theorem. Knowing you don't know is what it's all about.

    Remember... just because you've found a set that isn't equivalent to one of the listed sets, doesn't mean that you've found a set outside the system. Equivalency isn't a very useful operation in set mathematics.

    As for cetainy of potential certainty and such... that's a different level entirely. We're not talking about whether you're certain o something. We're talking about whether you know it. To be certain of it, you HAVE to know that you know it.

    Actually, I don't want to have this conversation without Venn Diagrams. I know your type.... you'll lose track.

  119. Re:The dawn of a new age of Math... and Science! by plasm4 · · Score: 0

    the art is long and life is short

  120. Already been done by rjw57 · · Score: 1

    The Four Colour Theorem was proved by a computer and hasn't been proved by a human since

    http://en.wikipedia.org/wiki/Four_color_theorem

    --
    Rich
  121. You can't trust computers nor mathematicians by AxelBoldt · · Score: 1
    Obviously, programs can contain logical errors, compilers can contain bugs, hardware can be faulty. So you can't trust computer calculations in proofs.

    However, you certainly cannot trust peer-reviewed human generated math proofs either. Virtually every mathematical article contains mistakes. Most of the time, these are small mistakes in the proofs that can be fixed in one afternoon. Occasionally there are gaps in proofs that take a couple of months to fill. And it also happens that the "proven" statements turn out to be completely false.

    So the best thing is a proof that humans have checked and that has been formalized and the formalization has been checked by a computer (like the Mizar people are doing). Of course, you cannot trust the results either.

  122. more than people by hak1du · · Score: 2, Insightful

    The mathematical literature is full of errors, oversights, invalid proofs, unstated assumptions, and probably even a certain share of deliberate fraud. See Lounesto's misconceptions of research mathematicians for one expert digging into the mathematical literature.

    Computers are far better at ferretting out oversights, missing assumptions, and making sure that every t is crossed and i is dotted. If a software system for doing proofs has shown itself to be fairly reliable on a bunch of samples, I'd trust it a lot more than I'd trust any working mathematician to carry out a complex proof correctly.

  123. verify by computer, then by hak1du · · Score: 1

    Actually, we don't have to "trust" them, we can verify the proof using proof verification software. And if you really get picky about it, you can verify the proof verification software using itself.

    The situation really is no different from numerical software. We perform long, tedious computations by computer, computations that we wouldn't trust any human to do correctly, if anybody even was willing to spend the time. We have software and methods for checking those numerical results. Well, mathematical proofs are no different.

  124. Was it? by werdna · · Score: 1

    Having a computer verify thousands of cases, and printing out the result, "PROVED!," doesn't so clearly add to our confidence in the proof. Of course, the Appel program gave more information than that, but it was fundamentally a case of a human relying upon a computer printout, quite uncritically, and assuming that a fundamental theorem had been proved.

    And this for a long-standing conjecture that had already been faced with plural examples of false proofs. While it was very exciting to see the "big four" fall, nobody had great confidence in the result.

    We don't have any proof that programs work today. How many tiny programs had you written and run, quite confident that the code would "just work," but ultimately needing to tweak it for awhile before it kicks? And then, a few days later, running into some obscure cases, needing to revise it to keep it running?

    I remember looking at that code while in grad school with an eye toward verifying it, or rewriting it with a proof-of-correctness in hand. While not shoddy code, it was no more beautifully well-written than any hacked lab code, and it did not inspire confidence that the code, when executed, would reveal fundamental truth.

    How helpful was it?

  125. Re:Shading even more towards OT, but oh well. by DarkSarin · · Score: 1

    I certainly agree with you, in every way. I was just stating that it was technologically feasible to verify the votes to a reasonable degree.

    We can't have it both ways, though. Either you have a voter ID or not. If not, then internet voting can NEVER be a reality.

    There are ways to make a vID without making it possible to run down who you voted for (but make my other suggestion impossible). You set the database to record if a particular ID has voted, but you keep the actual votes separate. Simple enough.

    --
    "We don't know what we are doing, but we are doing it very carefully,..." Wherry, R.J. Personnel Psychology (1995)
  126. peer review by Kent+Simon · · Score: 2, Insightful

    People attempting the proofs are no less vulnerable to making mistakes than those who wrote computer software to develop the proofs. Thus a system to verify the proofs should be in place for both groups of people. Any person working on a doctoral discertation will have their work reviewed by a board. Any proof generated by a computer shout too be reviewed by a board before it can be considered correct. I don't see where the issue is.

    --
    Kent Simon Multitheft Auto
  127. Frank Herbert's vision by kilimangaro · · Score: 1

    Thou shalt not make a machine in the image of Man's mind
    - From the Butlerian Jihad

    --
    "Insanity in individuals is something rare, but in groups, parties, nations, and epochs it is the rule." - Nietzsche
  128. 0! by Anonymous Coward · · Score: 0

    I thought 0! was usually, but not necessarily, defined to be 1.

    GrimRC

  129. Re:The dawn of a new age of Math... and Science! by PhotoGuy · · Score: 1
    All I'm saying is that the amount of knowledge and skills the average human being can possess will not increase expontentially over time (barring artificial manipulation). We gain new skills as a population and lose old ones.

    Just like the time I took that wine making course, and forgot how to drive.

    (Okay, okay, I promise that's the last time I'll make that joke.)

    --
    Love many, trust a few, do harm to none.
  130. MOD PARENT UP by Mark+of+THE+CITY · · Score: 1

    There's a BIG difference between memorization and doing well on homework and exams, and creating knowledge!

    --
    The clearance system sounds logical. It is not. It is completely arbitrary. -- John Bolton
  131. That's true of many bosses... by Bansuki · · Score: 1
    including Rumsfeld's. Or was that your original meaning?

    Anyhow, that's how I explain the "majority" that support(ed/s) our egregious actions overseas.

  132. Re:Faith vs Science (math?) by elhaf · · Score: 1

    It's called axioms. Those are the faith of mathematics. Goedel proved formal systems such as logic or set theorey based on axioms, and used in proofs are incomplete, so in the end we have already out-thought ourselves, 70 years ago. But Science != Mathematics. Science is much more pragmatic, and always knows that it doesn't know every thing, and is ideally always ready to have its foundations removed and replaced by something even more difficult to understand. We put faith into science because it works. In the end, the same thing goes for mathematics. The universe is not compressible.

    --
    Six score characters.
    Brevity being wit's soul
    I have enough space.
  133. We all know how that one ends up by PetoskeyGuy · · Score: 1

    The obvious solution is to have the computer create a new proof that shows that the algorithm it used to create the original proof is, in fact correct.

    And to prove that the proof of the proof can be trusted, have the computer create a proof of the proof of the proof.

    And to prove that the proof of the proof of the proof can be trusted, ...

    ...

    ...
    ... 42

  134. Are computers ready to solve proofs? by Anonymous Coward · · Score: 0

    Like 99.5% of slashdot it AT ALL qualified to answer this question.

    News for Nerds, knowledge a mile wide, but an inch thick.

  135. Re:The dawn of a new age of Math... and Science! by Mr.+McGibby · · Score: 1

    All I'm saying is that the amount of knowledge and skills the average human being can possess will not increase expontentially over time (barring artificial manipulation). We gain new skills as a population and lose old ones.

    True, but the reason that teenagers can understand calculus isn't because they're smarter, or because they have more "room" in their heads, it's because we understand calculus better now and can explain it in simpler terms. People tend to overlook advances in teaching methods that help new learners understand the same concepts with less complexity.

    As advanced concepts become old, better ways of teaching them will become available. And as students come to the table with a simpler understanding of the same stuff, they will be better prepared to create new theories.

    --
    Mad Software: Rantings on Developing So
  136. Alternate square packing by InvaderSkooge · · Score: 1
    I don't know the proof of this in general (and it's certainly not true for all rectangles, for example, ones whose lengths are integer multiples of the length of the square), but I can convince you it's true for some rectangles.

    Suppose your squares are all 1x1 (arbitrary units, if it helps let it be meters). Now consider a box that is 2.9x2.9. If you stack the squares straight starting on the bottom, you can fit four. But turn them 45 degrees, you can fit five, as the hypotenuse (for lack of a better word) of a square is only sqrt(2) (by the pythagorean theorem), and 2.9 > 2*sqrt(2), which leaves you with an empty space in the middle you can stick a fifth square in:

    I / \ / \ I
    I \ / \ / I
    I / \ / \ I
    I \ / \ / I

    And certianly any rectangle N+2.9xM+2.9 where N and M are integers, this is true in, as you can stack the rest in the normal way but use one corner to do this in. I suspect, however, that there are better tiling patterns for larger sizes.

    --
    Erik
    YOU ARE SAYING IMPUDENCE TO ME! THAT IS IMPUDENCE!
    1. Re:Alternate square packing by ahem · · Score: 1

      Very cool. Definitely thinking outside the box (so to speak). Thank you. I hadn't really considered rotating the squares, since that would leave you with a gap to start off with, but I didn't think about the idea that the optional loss of space would be less than the mandatory loss due to the relative sizes of the squares/box... very cool, indeed.

      --
      Not A Sig
  137. Let us restate the question... by bagsc · · Score: 1

    Does there exist an error in the complex computer manufactured proof? Suppose this is true. Now find the contradiction.

    Do programs have bugs? Do we use programs anyway?
    These are left as an exercise for the reader.

    --
    http://www.accountkiller.com/removal-requested
  138. Trunkated Known-Unknown Infinite Series by debipg · · Score: 1

    Actually this is an infinite series of two variable. lim n-> infinity [K^n+K^(n-1)U+ ... + K^(n-r)U^(r) + ... + U^n] You have written considering n=2.

  139. The Way of the Sufi. by Idries Shah by Anonymous Coward · · Score: 0

    its from a sufi recital (sarmoun ecital as the book calls it), you can still get the book from
    amazon

  140. conway? by tcteo · · Score: 1

    conway doesn't like computers? i'd like to see someone play his game of life by hand.

  141. Galois created Galois Theory by Anonymous Coward · · Score: 0

    Hence the name.

    Look it up, though - fun story. Galois died at age 20...in a duel over a woman. His papers from the previous 3 years spawned Galois Theory, which to this day is a pain in the ass to learn. :)