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Famous Hawking Black Hole Bet Resolved?

Mick Ohrberg writes "In 1997 the three cosmologists Stephen Hawking, Kip Thorne and John Preskill made a famous bet as to whether information that enters a black hole ceases to exist -- that is, whether the interior of a black hole is changed at all by the characteristics of particles that enter it. It now looks like Stephen Hawking and Kip Thorne may owe John Preskill a set of encyclopedias of his choice, since physicists at Ohio State University 'have derived an extensive set of equations that strongly suggest that the information continues to exist -- bound up in a giant tangle of strings that fills a black hole from its core to its surface.'"

57 of 400 comments (clear)

  1. Hawking radiation by Space+cowboy · · Score: 5, Informative

    Steven had posited in the 70's that the black holes leak (Hawking radiation), but the paradox is that they radiate a 'black-body' spectrum (entirely thermal radiation) in inverse proportion to their mass (so as they get smaller, the radiation increases). The problem here is that all the information went in, but it's very difficult to infer information from a black-body radiated spectrum (!). Steven therefore thinks that information is lost forever.

    The article though is a bit hand-wavy over why the information is preserved in this new theory... (I guess Nth dimensional maths doesn't appeal to the reporter :-). I don't think the fact that the string-theory radius matches the black-hole radius is sufficient to prove the case, though it's an interesting pointer, a curious coincidence if indeed it is such ...

    Effectively this is a conjecture - if the strings continue to exist, then they'd have the same size as the black hole appears to have. The throwaway statement " That means a black hole can be traced back to its original conditions, and information survives." seems a bit of a stretch though :-)

    Simon

    --
    Physicists get Hadrons!
    1. Re:Hawking radiation by Gil-galad55 · · Score: 5, Funny

      In my physics experience, coincidence typically means you got the right answer... unless it's a test question, in which case you're probably wrong.

      --

      To follow knowledge like a sinking star, / Beyond the utmost bound of human thought. ("Ulysses", Tennyson)

    2. Re:Hawking radiation by dandelion_wine · · Score: 4, Funny

      No, NO, Space_Cowboy, you have got it ALL WRONG.

      Now I want you to repeat after me:

      - First
      - Post
      - !

    3. Re:Hawking radiation by kfg · · Score: 5, Insightful

      My experience is that that sort of coincidence is suggestive, in other words you've gotten something right, but determining just what that something is is often a)problematic, and b)not always what you thought it was at first.

      KFG

    4. Re:Hawking radiation by Gil-galad55 · · Score: 5, Insightful

      And then there are the times when you get lucky and get the right answer for the wrong reason... which is, I suppose, why we have peer review!

      --

      To follow knowledge like a sinking star, / Beyond the utmost bound of human thought. ("Ulysses", Tennyson)

    5. Re:Hawking radiation by SeanTobin · · Score: 5, Interesting

      The thing about black holes emiting radiation is that they don't actually emit any radiation. Anything that enters the event horizon is gone - for good. It doesn't come back ever, even as black body radiation.

      The way theorists get around this is through virtual particles. Assume that virtual particle pairs are blinking in and out of existance all the time, but are never noticed because before they become 'real' particles they destroy each other (think particle/anti particle). The fun part comes when the particles appear on opposite sides of an event horizon. One gets sucked into the black hole, and the other becomes a full-fledged particle with a small chance of escapeing. Because the escapeing particle was never in the event horizon to begin with, it can contain no information from within the black hole.

      Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure... I'll leave that up to all the ./ theoretical physisists.

      --
      Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
    6. Re:Hawking radiation by dnoyeb · · Score: 5, Insightful

      In my mathematical experience, coincidence usually means you have used circular logic/calculations somewhere. In effect proving your foundation.

      But its always nice to figure out how you fooled yourself :)

    7. Re:Hawking radiation by kfg · · Score: 5, Funny

      Damn that peer review. The Nobel board laughed at me when my theory was submited, but I'll show them. Yes, I'll show them.

      Mwuhhahahahahahha!

      KFG

    8. Re:Hawking radiation by smittyoneeach · · Score: 5, Funny

      Because you are right, your loose definition of tautology is true.

      --
      Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
    9. Re:Hawking radiation by CAlworth1 · · Score: 5, Informative

      IANATP (theoretical physicist), but I think I may be able to shed a bit of light on the last question.

      As I understand it, the idea is that the particle and the anti-particle come into being at the same place, moving in different dirrectsion, and the anti-particle is more prone to being pulled in somehow due it its being the opposite of the other mass in the black hole. The particle escapes, generating the black-body radiation, and the anti-particle enters the black whole and collides with a corresponding particle, leaving existance as the original particles came into existance - messed up I know.

      If anyone is curious, (stolen from The Universe in a Nutshell by Stephen Hawking, the temp of a black hole is

      Temp = (h * c^3)/(8 * pi * k * G * M)

      where h is planck's constant, c is the speed of light, G is Newton's gravitational constant, k is Boltzman's costant,T is temp, and M is the mass of the black hole.

    10. Re:Hawking radiation by nihilogos · · Score: 4, Informative
      The article though is a bit hand-wavy over why the information is preserved in this new theory...

      The abstract from the NPB article is

      • It has been found that the states of the 2-charge extremal D1-D5 system are given by smooth geometries that have no singularity and no horizon individually, but a `horizon' does arise after `coarse-graining'. To see how this concept extends to the 3-charge extremal system, we construct a perturbation on the D1-D5 geometry that carries one unit of momentum charge P. The perturbation is found to be regular everywhere and normalizable, so we conclude that at least this state of the 3-charge system behaves like the 2-charge states. The solution is constructed by matching (to several orders) solutions in the inner and outer regions of the geometry. We conjecture the general form of `hair' expected for the 3-charge system, and the nature of the interior of black holes in general.


      If your institution is a subscriber you can get the full text from here

      --
      :wq
    11. Re:Hawking radiation by ralphclark · · Score: 5, Informative
      Because the escapeing particle was never in the event horizon to begin with, it can contain no information from within the black hole.

      Except that the pair of virtual particles are an entangled pair and if one catches the escaped one and measures its quantum state, one then knows the quantum state of the one that fell in. Catch enough of them and you know about an appreciable fraction of the black hole (in theory!)

      Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure

      The energy that was used to create the virtual pair came from the black hole's gravitational field, thus robbing the hole temporarily of mass. For each "virtual" particle that escapes as Hawking radiation, that mass is lost permanently so the mass of the hole goes down, over time. Now remember that this loss can only happen at the event horizon; if the black hole is very large, the tidal force (the gravity gradient) at the event horizon will be weak and thus the rate of particle loss will be very low. For very small black holes the tidal force at the event horizon will be enormous and almost all virtual pairs close to the boundary will separate in this way.

      So large black holes will simmer coldly, shrinking only with glacial slowness if at all, and small ones will be hot and shrink very rapidly indeed - finally disappearing altogether in an brief, intense burst of radiation, according to Hawking's theory.

    12. Re:Hawking radiation by krlynch · · Score: 4, Informative

      Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure...

      The black hole doesn't gain mass, because the particle that fell in has negative energy. Remember, you can't create energy from nowhere, but you can "borrow" some from the vacuum temporarily ... that's where the virtual pairs come from. They borrow energy from the vacuum, which they have to give back after a time (roughly) Delta T < hbar/E, where E is the energy of the particle pair.

      Now, if one half of the pair falls across the event horizon, it isn't coming back. The particle that escapes the hole becomes "real" because it has no one to annihilate with, so it carries off energy E/2. But since you can't yank energy out of the vacuum indefinitely, the particle that fell in had to be carrying energy -E/2 ... which isn't a problem, because it isn't a "real" particle, so it's energy need not be consistent with your expectations from freshman physics.

      So, where does that energy E/2 that goes into the escaping particle come from? The only place it can: the black hole. Remember, a negative amount of energy fell in. So the hole has to lose some mass in the process. Which is why we say that the black hole "emits" particles.

      The mathematical details are, of course, much nastier than that, but that's the gist of things...

    13. Re:Hawking radiation by CheshireCatCO · · Score: 5, Interesting

      Careful there. A simple-minded Newtonian derivation gives the correct Schwartschild radius for a black hole, despite having two deep physical flaws and relying on completely inapplicable physics. For that matter, two words: "Bode's Law."

    14. Re:Hawking radiation by rpresser · · Score: 4, Informative

      You misunderstand.

      A particle and an antiparticle both have a positive mass. The "virtual particle" mechanism means that for periods of times short enough, the measurement of the space right outside the hole is uncertain enough that there "might" be a pair of antiparticles there. So they are there. While they're there, one of them falls into the hole - it doesn't matter which one - while the other gains potential energy from its mate falling in, and escapes. Yaay.

      But you can't get something from nothing. Some mass escaped from the vicinity of the hole, so some mass has to disappear from the vicinity of the hole. So the hole loses mass.

      How's that for handwavy?

    15. Re:Hawking radiation by orin · · Score: 5, Insightful

      Actually a lot of complex experiments (unless they come up with something totally unexpected like Cold Fusion) - are not reproduced.

      The reason is that it is difficult enough to get funding for a complex experiment at the best of times. If you try to get funding to perform a complex experiment that someone else has already performed, you are a lot less likely to be successful.

      So although the theory is that scientific experiments are always directly replicated, in most cases scientists don't have the will (why go where someone has gone before) or the funds to do so.

    16. Re:Hawking radiation by maxwell+demon · · Score: 4, Funny

      Other way:

      a = b + c
      a(a - b) = (b + c)(a - b)
      aa - ab = ba - bb + ac - bc
      aa - ab - ac = ba - bb - bc
      a(a - b - c) = b(a - b - c)
      a = b

      Now:

      5 = 4 + 1

      This is undoubtedly true, and it's the first equation with a = 5, b = 4, c = 1.
      Therefore also the last equation is true:

      5 = 4

      Finally, use that equation with

      2 + 2 = 4

      and you've got

      2 + 2 = 5

      quod erat demonstrandum.

      Now, to proof that we have really truth, let's proof the central equation (i.e. 5 = 4) again in a completely different way:

      -20 = -20 (obviously true)
      25 - 45 = 16 - 36 (just rewrote the numbers as differences)
      25 - 45 + 81/4 = 16 - 36 + 81/4 (added 81/4 on both sides)
      (5 - 9/2)^2 = (4 - 9/2)^2 (used binomic formula)
      5 - 9/2 = 4 - 9/2 (took the square root)
      5 = 4 (added 9/2 on both sides)

      So, agan we have 5 = 4, using a completely diffferent proof. Now, this clearly shows 5 = 4 is true, and therefore also 2 + 2 = 5.

      --
      The Tao of math: The numbers you can count are not the real numbers.
  2. stephen lost by squarefish · · Score: 5, Funny

    and he looks really pissed about it too.

    --
    Creationists are a lot like zombies. Slow, but powerful and numerous. And they all want to eat our brains.
  3. Re: encyclopaediae by gnu-generation-one · · Score: 5, Funny

    "Stephen Hawking and Kip Thorne may owe John Preskill a set of encyclopedias of his choice"

    Do they take Wiki?

  4. status of string theory by microbox · · Score: 5, Interesting

    Is there any hard evidence that string theory is correct?

    I'd be holding onto my bet a little longer I think=)

    --

    Like all pain, suffering is a signal that something isn't right
    1. Re:status of string theory by Anonymous Coward · · Score: 5, Informative

      Responding as I am taking a string theory course from Prof. Zwiebach here at MIT ...

      String theory certainly does predict a number of things that are easily testable ... just not right now. For instance, compactified extra dimensions (as SR includes) introduce additional energy terms to simple quantum problems (i.e. "particle in a box" problems, and SHOs). The problem is that these effects are very large; ergo, the energies necessitated to test these theories are somewhat higher than we can accomplish.

      Yes, it's a theory, yes it's kinda off-the-wall and feels a bit contrived, but, studying it, I gotta say that it's pretty if nothing else. It's elegant enough and compelling enough - in terms of what it promises to explain - that it's worth following until it's found to actually be wrong.

      A quantum theory of gravity might not be so motivating to you, but if you're a physicist, it's worth trying something wonky to get to it. (Speaking of which, Quantum Loop Gravity - also very wonky - is awesome).

      And, as for "quite a few people" finding it too philosophical ... well, quite a few people aren't physicists. *shrugs*

  5. Tangle of strings? by ENOENT · · Score: 5, Funny

    Yikes! Sounds like all information that enters a black hole turns into spaghetti code!!! The horror! The horror!

    --
    That's "Mr. Soulless Automaton" to you, Bub.
    1. Re:Tangle of strings? by DoctorScooby · · Score: 5, Funny

      Yikes! Sounds like all information that enters a black hole turns into spaghetti code!!! The horror! The horror!

      Now I know where Windows98 really came from.

  6. Of course by FreeLinux · · Score: 5, Insightful

    This all works on the assumption that you accept string theory in the first place. While string theory may be the darling of astro physicists at the moment, it remains far from proven. If I were Haking, I'd defer payment for a while.

    1. Re:Of course by Bingo+Foo · · Score: 4, Insightful

      String theory has not been proved, but neither has any physical theory. Perhaps you are complaining that unlike other physical theories, it is unlikely that an experimentally accessible test for disproving string theory can be found. This makes string theory not really "science," in the sense that we normally understand it.

      Additionally, people's names are conventional rather than scientific, but their legal usage has necessitated their meticulous recording. While it can't be proven, it can be verified beyond a reasonable doubt that the Lucasian Chair of Mathematics at Cambridge is Stephen Hawking.

      --
      taken! (by Davidleeroth) Thanks Bingo Foo!
  7. Re:Is it me by microbox · · Score: 5, Insightful

    Maybe the real workings of the universe can't be explained with everyday experiences. After all, quantum stuff and relativity has little bering on hunting, communicating and making little ones, and that's what our brains were designed to do.

    --

    Like all pain, suffering is a signal that something isn't right
  8. Tracing origins... by Theaetetus · · Score: 5, Insightful
    From the article: Since Mathur's conjecture suggests that strings continue to exist inside the black hole, and the nature of the strings depends on the particles that made up the original source material, then each black hole is as unique as are the stars, planets, or galaxy that formed it. The strings from any subsequent material that enters the black hole would remain traceable as well.

    That means a black hole can be traced back to its original conditions, and information survives.

    But, if the information about the origins is contained in the strings inside the black hole, that information is inside the event horizon, and can not be observed by anything outside the event horizon. Maybe the information survives, but there's no way to get at it... Unless I'm missing something here? Cosmologists?

    -T

    1. Re:Tracing origins... by Tumbleweed · · Score: 4, Funny

      > Unless I'm missing something here? Cosmologists?

      "Is there a cosmologist in the house? Anyone? My god, get this man a cosmologist!"

  9. Let's get closer... by Lattitude · · Score: 5, Funny

    I say we send someone to find out for sure... Darl, you interested?

    1. Re:Let's get closer... by McBride,+Darl · · Score: 4, Funny

      Yes.

      --
      Darl McBride
      Chief Executive Officer
      Caldera International, Inc.
  10. Re:Is it me by NotQuiteReal · · Score: 4, Funny
    Yes, it is just you. I knew everything, once - it came to me in a flash of insite... then, incoming email chimed for my attention, I read some spam, had another beer and read Slashdot until something on TV caught my eye.

    Now, I forgot what it was that I thought I knew.

    --
    This issue is a bit more complicated than you think.
  11. As soon as we figure out how to retrieve ... by burgburgburg · · Score: 5, Funny

    the information in the black hole, we'll finally find Amelia Earhart. And Jimmy Hoffa. And hundreds of millions of socks. And Duke Nukem Forever.

    1. Re:As soon as we figure out how to retrieve ... by psoriac · · Score: 5, Funny

      And Duke Nukem Forever.

      Hey, this is theoretical physics, keep your pseudo science out of here!

      --
      I browse Slashdot at +3, Funny
  12. Tangle of Strings by Gleng · · Score: 5, Funny
    bound up in a giant tangle of strings that fills a black hole from its core to its surface

    Sounds like the back of my desk!

    --
    "Proudly Posting Without Reading The Article"
  13. Re:Is it me by Pingular · · Score: 4, Insightful

    Maybe the real workings of the universe can't be explained with everyday experiences. After all, quantum stuff and relativity has little bering on hunting, communicating and making little ones, and that's what our brains were designed to do.
    To me, it makes more sense that the real workings of the universe would be incredibly simple rather than complex. Not sure why, it just seems to make sense :)

    --

    When anger rises, think of the consequences.
    Confucius (551 BC - 479 BC)
  14. Re:Is it me by E-Rock · · Score: 4, Funny

    I found that in physics, going with 'common' sense or your gut was a good way to look stupid while making it obvious that you didn't review the lecture material the night before.
    On the flip side, the math always did a hell of a job predicting the outcome of experiments.

  15. Re:Sweet by Lehk228 · · Score: 5, Funny

    FAT32 is a pretty good data singularity, goes in but won't come back out

    --
    Snowden and Manning are heroes.
  16. *sob* It must be so sad in there. by Andy+Smith · · Score: 5, Funny
    the information continues to exist -- bound up in a giant tangle of strings
    Aw! Information wants to be free.
  17. You're more right than you think by Raul654 · · Score: 4, Interesting

    Jimbo Wales (founder / benevolent dictator of Wikipedia) was recently approached by a major publishing company about the possibility of a printed version of Wikipedia.

    --


    To make laws that man cannot, and will not obey, serves to bring all law into contempt.
    --E.C. Stanton
    1. Re:You're more right than you think by BabyDave · · Score: 4, Funny

      Jimbo Wales (founder / benevolent dictator of Wikipedia) was recently approached by a major publishing company about the possibility of a printed version of Wikipedia.

      Will it come with a free bottle of correction fluid and a pen?

  18. Re:Simple question maybe by benna · · Score: 5, Informative

    Why not consult Official String Theory Web site :)

    --
    "It is not how things are in the world that is mystical, but that it exists." -Ludwig Wittgenstein
  19. all those lost by that article, raise your hands.. by The+Other+White+Boy · · Score: 4, Funny

    *raises hand*

  20. Re:Is it me by mugnyte · · Score: 5, Insightful

    I don't understand this at all. Our everyday experiences are simply products of the "real workings" of the universe. You may think Newtonian physics suffices for what you need, but your "little ones" wouldn't be able to dream of being an astronaut, science professor, astronomer, or a myriad of other things without these other new-fangled theories.

    When we achieve enough proficiency in our understanding to make accurate predictions, and validate them with observations, then publish them, have them scrutinized publicly and repeated, we're making vast improvements to the knowledge humanity holds. The fact that we're in so esoteric topics for new things at the moment just goes to show how valid this system is; we've built a cohesive worldview in physics down to the quantum level. There, mysteries abound, but it doesn't mean we shouldn't be there.

  21. Information? Not Matter? by ackthpt · · Score: 5, Funny
    In 1997 the three cosmologists Stephen Hawking, Kip Thorne and John Preskill made a famous bet as to whether information that enters a black hole ceases to exist

    Slashdot, where information goes to die.

    --

    A feeling of having made the same mistake before: Deja Foobar
  22. Wow, what a gig by digrieze · · Score: 4, Funny

    I have to change careers. These physicists (sp?) have just created the biggest manefestation of a quantom physics illustration ever (namely scrondiggers (sp?) cat). The black hole is the box, the information entering the event horizon is the cat. Anything at the singularity is not observable and is therefore in a permanent state of flux between states (not really, but our ignorance of what's going on creates that condition). When we make observation our predispositions on the data influence the observation and change the reality. In other words YOU CAN'T BE WRONG NO MATTER WHAT YOU SAY!

    Is there some way I can get this gig?

    --
    It doesn't matter what you wrap your emotions around, Reality is a brick wall specifically designed to scramble eggs
  23. Almost - wrong bet though by Raul654 · · Score: 5, Interesting

    Hawking has made several bets. You are thinking of his naked singularities bet (A naked singularity is a black-hole without event horizons) Hawking bet Roger Penrose(?) a subscription to Penthouse (I think) that they could not exist. He lost.

    --


    To make laws that man cannot, and will not obey, serves to bring all law into contempt.
    --E.C. Stanton
  24. Re:Simple question maybe by Anonymous Coward · · Score: 4, Interesting

    A very tiny dimension all curled up on itself as opposed to extending to infinity (like we're typically familiar with). If a foam in a bubble bath is the whole universe, a bubble in the foam might be analogous to a string. Space is soap, we're not allowed to see it directly, but we can see its effect.

    String theory has modest successes with some things, and monsterous problems with others. It's essentially built to explain why gravity is so weak. At distances smaller than strings gravity is as strong as all the other forces. But it doesn't overwhelm everything at large scales because gravity is the only force which can see the strings, and so it leaks off into these other dimensions untimately becoming very dilute.

    The hope of theoreticall physicists is to unite gravity with the other forces, understanding everything about it's divergance, hopefully uniting quantum electro/chromodynamics with general relativity creating one theory to explain them all, and, in mathmatics, bind them.

  25. Oh really, come on, get a clue! by Jerf · · Score: 4, Interesting

    It is often... though not often enough... pointed out that the singular of "data" is not "anecdote".

    Similarly, "fact" is not merely an emphatic form of "theory".

    I might as well theorize that black holes don't exist at all; who owes what now? Oh, right, nothing changes, because theories aren't facts .

    Mick Ohrberg, why don't you grow out of Physics Fanboydom and take some time to learn some real stuff? For starters, why don't you being with Science 101 and learn the definition of "theory", and "equation", and other such basic terms?

  26. What it doesn't say. by DynaSoar · · Score: 4, Interesting

    I can buy that the information survives and continues to exist inside the Schwarzchild radius.
    But when they say:

    "The strings from any subsequent material that enters the black hole would remain traceable as well. That means a black hole can be traced back to its original conditions, and information survives." ... they're going to have to explain a bit harder just how it is we're supposed to be able to extract that information back out through the event horizon. Whether it continues to vibrate on linked strings or vanishes in a puff of nonreality makes no never mind if you can't get it back out.

    --
    "I may be synthetic, but I'm not stupid." -- Bishop 341-B
  27. Mathur's tests by trip11 · · Score: 5, Interesting
    I've actually had Mathur for classes as I'm an undergraduate at Ohio state in physics. His tests really are not all that brutal as he is both an amazingly smart man and a good teacher. He has this dry humor that you have to pay attention to to get. Amusing quips include:

    "It will be a big piece of fun" (talking about deriving equations)

    "thats a rather large force" (after mentioning that the force to pull two pieces of a capacitor apart could lift the city of columbus)

    If you get a chance to meet him, don't pass it up. He's a great guy

  28. Black Hole Interior by whig · · Score: 4, Interesting

    Perhaps the information survives in the black hole interior. Physics infers a black hole by an event horizon, but that does not necessarily imply a singularity. On the other hand, if the interior is considered as a "universe" with its own set of physical laws and structure, this conjecture could be quite relevant.

    For a somewhat handwaving explanation of what I'm talking about, take a look at this hypothesis.

    --
    Peace and love, y'all
  29. Blackt holes shown to compress losslessly. by Canthros · · Score: 5, Funny

    Decompression support expected in next WinZip release.

    --
    Canthros
  30. The conclusion may be wrong by jd · · Score: 5, Funny
    I can prove that if you pour information into Congress, you end up with a tange of red tape, which is similar to a superstring. (Red tape is used to hold things together that would otherwise fly apart; red tape requires at least 10 more dimensions to exist; and there is some evidence that particles of beaurocracy have negative gravity.)


    However, there is no proof that any of the information survives, after being caught up in red tape. Indeed, all evidence so far suggests that it does not.


    (Beurocracy particles are a subclass of Strange Quarks that have beeen influenced by a politic Ion)

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  31. Re:Is it me by mindstrm · · Score: 5, Insightful

    Part of the problem is the language used to describe these things.. the general approximations they make only really make sense if you understand a lot more background..

    On the surface this might all seem like philosophical banter... but that's just what the news prints. What is behind this is tons of chalkboards and computers full of equations that fit modern theory.

    Remember, we don't HAVE a theory of everything yet... i'ts not like everything is perfect, and scientists are trying to make things up to look smart.. there is a point where our current equations don't add up, don't make sense.. and that's where these guys are working now.

    superstrings, quantum gravity, etc.. these aren't whimsical sci-fi dreams.. they are where science is currently trying to figure things out.

  32. Next on "Ask Slashdot" by the+cobaltsixty · · Score: 4, Funny

    "What's the most expensive encyclopedia you've ever seen?"

  33. Re:Is it me by wass · · Score: 4, Informative
    ike they're so determined to make something make sense, they blindly look for something that'll fit the problem, even if it's obvious that it's probably not right

    I actually recently responded to a similar accusation against physicsists, and you can read my reply here . That response has more examples listed of 'kludges' in physics, but I'll talk about a few in more depth in this post.

    What you've just described is known as phenomenology. In other words, trying to come up with some sort of basic theory to match the given data. Examples include Planck's original quantizing of radiation into discrete quanta, which turned out to be right. Another example is the Landau theory of 2nd-order phase transitions, where one builds a power-series expansion of the free energy in powers of something called the 'order parameter'. This is a total hack, but in many cases can adequately describe phase transitions (including superconductivity).

    In fact, there are many kinds of physics theories, some termed 'macroscopic' in which case they're phenomonoligical, and describe what's going on, but don't adequately describe the 'physics' of the system. Then there's the microscopic theories that talk specifically about particle interactions, and follow directly from quantum mechanics, statistical mechanics, E&M, etc. The goal is to make these two approaches mesh.

    For example, superconductivity could be described fairly well using the Ginzberg-Landau expansion, where the order parameter described above is complex, instead of real. Many things can be described this way, including Josephson Junctions and fluxoid quantization of superconducting loops. (Ginzberg just won the Nobel Prize in physics in 2003. Landau, if he were still alive, would have probably won it too, and it would have been his 2nd physics nobel prize). This approach worked fairly well, but physicists weren't sure why that was.

    But then in 1957 Bardeen/Cooper/Schrieffer came up with the BCS theory of superconductivity, which explicitly describes how the electrons can pair up into Cooper pairs. Electrons want to repel, but in the right crystal lattice an electron-phonon-electron interaction (ie, a local distortion of the lattice) can produce an attractive interaction. BCS describe how this attraction comes about, how the energy gap forms, and how the electron pairs can carry a resistanceless supercurrent. BCS won the Nobel Prize in Physics in 1972.

    This was microscopic vs macroscopic development of superconductivity. Two years later, physicist Gor'kov was able to show that the Ginzberg-Landau theory comes as a limiting case of the BCS theory. Hence, microscopic meets macroscopic, and everybody's happy.

    So yes, physicists do look for something to fit the problem, but they don't just stop there. They also try to make those hacks or kludges match up directly from physical laws of the universe. That's what physics is about.

    --

    make world, not war

  34. Ironic Science by Ralph+Spoilsport · · Score: 4, Interesting
    First: I think String theory is probably correct HOWEVER:
    Second: I can't see how you can possibly test any of this.

    If you can't test it, then it's just a likely story. It might be a more likely story than saying little green elves did it all, but in essence, it;s not that different.

    Tangles of strings - Suuuure.

    As I said, it probably is true, and string theory is a lot cleaner, but damn - what are you going to do? Crack open a black hole to find out?

    We. don't. think. so.

    It strikes me as what Horgan calls "Ironic Science".

    RS

    --
    Shoes for Industry. Shoes for the Dead.