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Frame Dragging by Earth Reconfirmed

smooth wombat writes "After 11 years of watching the movements of two Earth-orbiting satellites, researchers found each is dragged by about 6 feet (2 meters) every year because the very fabric of space is twisted by our whirling world. The results, announced today, are much more precise than preliminary findings published by the same group in the late 1990s. The researchers say their result is 99 percent of the predicted drag, with an error of up to 10 percent. The details are reported in the Oct. 21 issue of the journal Nature."

379 comments

  1. networks by OwlofCreamCheese · · Score: 4, Funny

    derr... my brain thought "what? frame dragging? story about networks or something?"

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    1. Re:networks by databyss · · Score: 5, Funny

      I thought it had to do with some new rendering techinique in HL2.... then i realized it was just boring old space-time stuff...

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    2. Re:networks by EvilTwinSkippy · · Score: 0, Offtopic

      What is really creapy. I was reading up on General Relativity earlier today.

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    3. Re:networks by britneys+9th+husband · · Score: 3, Funny

      You were on the right track the first time. It's actually a new rendering technique they're using in the matrix.

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    4. Re:networks by SavingPrivateNawak · · Score: 1

      I think the link in your sig will not attract many /.ers... Come on... HotTubGirl?
      Tubgirl is a click repellent word around here...

    5. Re:networks by Anonymous Coward · · Score: 0

      Click repellant? You clicked on the "reply" button, didn't you?

      UOB. LUY. UNAQ.

  2. Isn't that... by pmazer · · Score: 2, Informative

    What one of the recent satelites was sent up to do?

    1. Re:Isn't that... by Anonymous Coward · · Score: 5, Informative
      Yes, the project is called Gravity Probe B, launched in mid-April 2004.


      -HJ

    2. Re:Isn't that... by Anonymous Coward · · Score: 0

      This one? Looks like they are a little late....

      <URL:http://einstein.stanford.edu/>

    3. Re:Isn't that... by nerdguy569 · · Score: 5, Informative

      No, this is different, Gravity Probe B is a separate project, this was an Italian research group who used freely avaliable data from the past 11 years of the two LAGEOS satelites, who's orbital paths have been monitored for that time. Space.com has a good summary, and so does New Scientist

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    4. Re:Isn't that... by MillionthMonkey · · Score: 0, Offtopic

      Why is it that the American government's style of attacking most technical problems seems to involve throwing a lot of money around and doing everything in the most grandiose and impractical way possible? It reminds me of the apocryphal story of the problem of writing in zero gravity, where NASA spent considerable money and resources to develop a pen that doesn't need gravity to feed the ink, and the Russians just took pencils.

      During WWII, the Manhattan Project had problems getting copper for the huge electromagnets that they needed to build. No problem- they just went to the Treasury, borrowed 15,000 tons of silver bullion, and wound it into coils! What other country on earth would even have been able to consider such a thing back then? The bomb was a bad thing, etc., but I've always felt sort of proud that I live in a country that's been able to actually do crazy things like that.

    5. Re:Isn't that... by Anonymous Coward · · Score: 0

      Will these dumb myths ever die? The government did not fund the space pen, a private company made it. Pencils are a terrible solution in space because graphite dust is a problem, among being an annoying dust which can clog up filters graphite has some electrical properties (I'm not sure exactly what properties but graphite dust can be used to smooth out a scratchy potentmeter or volume knob which would seem to be improving the connection).

    6. Re:Isn't that... by MillionthMonkey · · Score: 2, Interesting

      Will these dumb myths ever die?

      Hey, I said the story was apocryphal. It may be BS but it persists because it captures a grain of truth about the way Americans approach major technical problems.

      Graphite is a conductor, so you don't want its dust floating around in a spaceship where it might short something out. Russian reactors (some of them) use graphite as a moderator, to slow down neutrons without absorbing them. We use heavy water. And there you go- that's another example. We go through all this trouble of separating isotopes, and the Russians just use the graphite from the pencils that they take into space! (Although there was that fire that one time, but never mind.)

    7. Re:Isn't that... by cetialphav · · Score: 1

      Why is it that the American government's style of attacking most technical problems seems to involve throwing a lot of money around and doing everything in the most grandiose and impractical way possible?

      Huh? There is a big difference between these two projects. The Gravity Probe B is going to provide a much more accurate measure (within 1%) as opposed to the 10% (and that is debatable) that was just done. There simply is no cheap way to get that extra certainty.

      Kudos to the researchers who came up with this. This looks like a good case of creative, outside the box thinking that gives some good information quickly and cheaply. But this still needs to be confirmed by an experiment where things are "done right".

      Your comparison is like saying DOS 6 is better than Linux 2.6 because it is the less bloated x86 operating system.

      But like you observed, we have the resources to do the job right. Why do half-assed science when we can afford to do an accurate job? It's not like we can repeat this over and over by sending up better and better satellites. These things are still expensive enough that we need to get it right the first time.

    8. Re:Isn't that... by Doc+Ruby · · Score: 1

      The myths persist more because of the believers assumptions than the "grain of truth" in the stories themselves. The survival of this one depends as much on the ability of Americans to spend lots of money on space research, because of popularity of the programs, ROI in military apps, and availability of lots of American money, as it depends on foreigners to be jealous of the American scene.

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    9. Re:Isn't that... by MillionthMonkey · · Score: 1

      Your comparison is like saying DOS 6 is better than Linux 2.6 because it is the less bloated x86 operating system.

      Oh I wasn't being down on Gravity Probe B. I even know someone who worked on it. It is a really sophisticated, incredibly complex and ambitious experiment, and like you said it's going to provide much more accuracy than this. (Just like pens are better than pencils.) But this does remove a bit of the suspense about what Gravity Probe B will find. The ideal situation would be if it produced a result outside the margin of error of the GR prediction. That way new physics comes out of it. This preliminary result somewhat reduces the chances of that happening.

    10. Re:Isn't that... by Anonymous Coward · · Score: 0

      who's orbital paths have been monitored

      "whose".

    11. Re:Isn't that... by nacturation · · Score: 2, Interesting

      During WWII, the Manhattan Project had problems getting copper for the huge electromagnets that they needed to build. No problem- they just went to the Treasury, borrowed 15,000 tons of silver bullion, and wound it into coils!

      What's really impressive is the transformation from silver into copper! :)

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    12. Re:Isn't that... by fatphil · · Score: 2, Funny

      Pencils fill the confined atmosphere with graphite dust. You don't want layers of graphite on your circuit boards.

      They US/SU should both have just used either wax crayons, or etchasketch.

      FP.

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    13. Re:Isn't that... by fatphil · · Score: 1

      Unless this preliminary result is the output of a cynical publish-or-perish mentality.

      Who would the resources to shoot this down if it were to be fraudulent? How long did Mendel yet away with his faked results? Exactly.

      FP.

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    14. Re:Isn't that... by fredrik70 · · Score: 1

      graphite as a moderator for a reactor is a Bad Idea. the RBMK as a design 'feature' that could very striong power output increase if coolant is lost. (positive void coefficient). the graphite can also ignite, In chernobyl it burned for 9 days and while doing so released radioactivity into the atmosphere.

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    15. Re:Isn't that... by infinite9 · · Score: 1

      Damn! Is there anything you can't do with LAGEO bricks?

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    16. Re:Isn't that... by JohnFluxx · · Score: 1

      "Hey, I said the story was apocryphal. It may be BS but it persists because it captures a grain of truth about the way Americans approach major technical problems."

      Your second example was also discounted by another poster. (Graphite is bad as a moderator because it ignites).

      Using bad examples for the "grain of truth" is just stupid. At least give a good example.

    17. Re:Isn't that... by Carnildo · · Score: 1

      Actually, silver is even better for the job than copper -- it's got about 2% lower resistance -- but the expense usually isn't worth the results.

      --
      "They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
    18. Re:Isn't that... by Anonymous Coward · · Score: 0

      > where NASA spent considerable money and resources to develop a pen that doesn't need gravity to feed the ink, and the Russians just took pencils.

      First of all, it's an urban legend. Secondly, graphite dust is NOT something you want floating around the electronics. A crayon is probably better, won't poke out someone's eye out either if you slip and fling it across the spacecraft.

      > they just went to the Treasury, borrowed 15,000 tons of silver bullion

      That's more bullion than there is on earth. Try again.

    19. Re:Isn't that... by Anonymous Coward · · Score: 0

      Are you sure that there isn't 15,000 tons of silver bullion on earth?

  3. Ouch... by tetranitrate · · Score: 4, Funny

    After 11 years of watching the movements of two Earth-orbiting satellites, researchers found each is dragged by about 6 feet (2 meters) every year because the very fabric of space is twisted

    The researchers say their result is 99 percent of the predicted drag, with an error of up to 10 percent


    I think my head just exploded

    1. Re:Ouch... by erikharrison · · Score: 2, Funny

      That's 'a splode'.

      Jeez. Get your obscure internet references correct prior to posting.

    2. Re:Ouch... by DigiShaman · · Score: 3, Funny

      You see...it has to do with the warping of space and time. It would seem that it also warps numbers too.

      --
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    3. Re:Ouch... by EvilTwinSkippy · · Score: 3, Funny

      Hence poll numbers.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    4. Re:Ouch... by Anonymous Coward · · Score: 0

      You know what they say about 'sex panther'... 60% of the time, it works all the time!

      (if you don't get it, watch Anchorman)

    5. Re:Ouch... by Anonymous Coward · · Score: 0

      They're 99% sure it's what they originally thought, and I'm 10% sure they're full of shit.

    6. Re:Ouch... by muyuubyou · · Score: 1

      That 10% comes probably from their obsession using imperial metrics :D

      6 ft -> 1.83 m
      2 meters -> 6 ft 5.6 inches

      There, your ~10%

    7. Re:Ouch... by Mwongozi · · Score: 1

      Bistromathics!

    8. Re:Ouch... by danila · · Score: 2, Informative

      May be you need to learn basic math? The result predicted by theory was 2.02 meters. Their measurement was 2 meters, but this is just an estimate and the correct result (real) should be between 1.8 and 2.2 meters (with a probability of something, such as 95 or 99% - not mentioned in the article).

      According to current results, the theory may be correct (may be even "is likely to be"). But of course, we need more precise measurements.

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  4. Why, this explains why.... by Tablizer · · Score: 5, Funny

    ....I can't find the @!#% TV remote. Time to diet, I guess.

    1. Re:Why, this explains why.... by ikkonoishi · · Score: 1, Offtopic

      Have you been spinning around a lot lately?

  5. GR lives on and on by metlin · · Score: 4, Interesting

    I was under the impression that there has been experimental evidence for the existence of Spin Distortions in Lense Thirring effect?

    This would mean that inward spiralling matter observed near black-hole like phenomenon were indeed valid physically.

    But as the Nature article points out, the accuracy of Ciufolini's work not yet certain, since the value is not absolutely the same as that predicted by relativity (only 99%, with an error of upto 10%). And anyway, the last major prediction of GR -- gravity waves -- is not yet done.

    So until then, three cheers for experimental physics!

    1. Re:GR lives on and on by jnik · · Score: 2, Insightful
      But as the Nature article points out, the accuracy of Ciufolini's work not yet certain, since the value is not absolutely the same as that predicted by relativity (only 99%, with an error of up to 10%)

      What are you looking for? There's no such thing as "certain." In fact, this result is excellent--with 10% error bars, I'd be ecstatic to agree with predictions within 1%.

      99% +/- 10% is far better than 99.9% +/- .01%

    2. Re:GR lives on and on by hazem · · Score: 1

      > 99% +/- 10% is far better than 99.9% +/- .01%

      Maybe... but when you compare the two, isn't 99.9% +/- .01% an indication that your process is better, or more precise?

      99% +/- 10% might get you within range of your prediction, but the more precise result may actually indicate that your predictions are not complete.

      As for me, I suppose I'd prefer my data and analysis be sound, even if it means I have to revise my predictions.

    3. Re:GR lives on and on by Phleg · · Score: 1, Insightful

      99% +/- 10% is far better than 99.9% +/- .01%

      Not at all. That +/- 10% is there for a reason. The margin of error is just that--a margin within which error could have occurred. The true value could easily have been 92% or 105% the predicted value, but the error caused it to become closer to what was expected. I'd be more interested in the latter example, as deviations that small usually indicate that we're on the right path with minor reworking.

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    4. Re:GR lives on and on by Anonymous Coward · · Score: 1, Funny

      In reality it is just the Vogons doing an interstellar highway survey. Guess what, we are in the way!

    5. Re:GR lives on and on by Kiryat+Malachi · · Score: 4, Informative

      You obviously don't understand margin of error. The large error suggests imprecise measurement, the central limit suggests that the end value will in fact be close to the predicted. 99% +/- 10% is more promising with regards to the theory than 99% +/- 0.01% would be.

      Statistics lesson.

      Margin of error is not a bound within which any result is equally likely. Depending on the distribution, it can be anywhere from equal likelihood (uniform distribution, which is extremely rare in natural processes) to single point (in which case the MOE is obviously zero, and the result is definitive.) For example, most things with a binary outcome (yes or no, 1 or 0, etc) follow what's known as the binomial distribution. If the probability of either result is equal, the binomial pattern is equivalent to the normal (Gaussian) distribution, which looks like a bell, and is produced by many processes, especially processes involved in noise and measurement error.

      Now, depending on the expected distribution this changes, but for a normal distribution the likelihood is probably 95% that the actual value is within that +/-10% (assuming they're using the typical definition of 2 sigma for margin of error) - but it's around 65% likely that the result is within +/- 5%, and the most likely single result is in fact 99% - not 99% likely, but the maximum likelihood points to 99%.

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    6. Re:GR lives on and on by nacturation · · Score: 1

      99% +/- 10% means that the theory is most likely correct as 100% falls within the expected values.
      99.9% +/- 0.01%, though a much more accurate experiment, means that the theory is certainly wrong.

      Therein lies the difference.

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    7. Re:GR lives on and on by Anonymous Coward · · Score: 0
      As for me, I suppose I'd prefer my data and analysis be sound, even if it means I have to revise my predictions.
      Isaac Newton thought his data and analysis was sound.

      Which proves... uh. Sorry, I forgot my point. My head asploided when it reached 109% of maximum capacity.
    8. Re:GR lives on and on by Anonymous Coward · · Score: 0

      You are entirely correct but please get your head out of your ass. We want precise answers and not just any answer that is imprecise but seems to confirm our theories.

      That's why 99% +/- 0.01% is better for science than 99% +/- 10%

      Read that line recursively until you get it, the rest of you too. It the point being made by the grandparent.

      I'm not the grandparent of this post (that guy didn't care enough to help you pry your head out) and I posted this AC because the replies are likely to be morons who really can't get it and I don't care for responding to those.

    9. Re:GR lives on and on by Kiryat+Malachi · · Score: 1

      FOR THE EXISTING THEORY, 99.9% +/- 0.01% IS NOT BETTER THAN 99% +/- 10%!

      The existing theory is more likely to be true under the less precise measurement. Of course we want precise measurements, but from the perspective of trying to confirm our existing theory we would like it to be within the margin of error and near the central limit.

      That was my point. Further, the poster who said it "could equally likely by 92% or 102%" was completely wrong, and people are just fucking dumb about statistics and need enlightenment.

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  6. Don't Get TOO Excited by the_mad_poster · · Score: 5, Informative

    Hmmm... I read this earlier because CNN jumped on it, but there are questions (noted in the Nature article) about its actual accuracy. There's some concern that the original gravity field maps that this method used weren't accurate enough.

    This is a good step forward, but I think until we call the frame dragging prediction confirmed we should wait to see what Gravity Probe B comes up with.

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    1. Re:Don't Get TOO Excited by metlin · · Score: 2, Informative

      Actually Frame Dragging is supposed to happen, just that there seems to be some doubts with regard to this experiment in particular.

      Besides, I was under the impression that Frame Dragging was already verified experimentally among certain other massive astronomical bodies out there.

    2. Re:Don't Get TOO Excited by the_mad_poster · · Score: 5, Interesting

      Frame dragging is the explanation for observed inconsistencies in the swirling gas/dust clouds surrounding massive black holes, but I don't know that this portion of the theory has ever been confirmed via experiment.

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    3. Re:Don't Get TOO Excited by metlin · · Score: 2, Informative

      You're right, except that it's theoretically observed around any massive body - even Earth.

      It's just that it is easier to observer the phenomenon around blackholes owing to their massive nature.

      It's just the -actual- curving of space-time around massive bodies that affect the way objects are drawn towards the massive body.

    4. Re:Don't Get TOO Excited by the_mad_poster · · Score: 2, Informative

      Agreed, but we're talking about two different things now. It's definitely been observed in the cosmos, but AFAIK this is the first experiment that tentatively confirms the phenomenon.

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    5. Re:Don't Get TOO Excited by metlin · · Score: 1

      Well, ofcourse.

      I get you now.

      What I meant was that this is merely an observation, there are some things in nature I do not quite think we can prove completely through purely experimental means except through observation.

      I suspect if even the LIGO and LISA experiments conclusively -prove- it experimentally, I think they are more of particular measurements and observation.

    6. Re:Don't Get TOO Excited by Rob+Carr · · Score: 5, Interesting
      It's just that it is easier to observer the phenomenon around blackholes owing to their massive nature.

      The problem with the black hole observations is that a number of guestimates need to be made. The guestimates are probably valid, but there's enough wiggle room that it's hard to say the effect is really there.

      The gravity maps that were used for this latest release are far more accurate than previous attempts to do this with the 11 years of data, and it seems to have confirmed that frame dragging does occur as per relativity.

      The Gravity B experiment will be one more proof of frame dragging - although no one really expected frame dragging to be disproved. There's too many other things about General Relativity that have been confirmed.

      Somewhere, General Relativity must break down so that it can match up with wherever Quantum Mechanics breaks down, permitting the two theories to be joined in some coherent fashion. But there's no way that frame dragging could be the place where General Relativity gives out. It's an experiment that needed to be done. It's dotting the i and crossing the t. But it's not worth much. That's the real debate. Should all the money have been spent on Gravity Probe B to prove something everyone accepts, or should other ways (like digging up 11 years of satellite data) have been used and the money spent on something that might actually give a bang for the buck?

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    7. Re:Don't Get TOO Excited by davidsyes · · Score: 2, Funny

      Existence is not necessarily based on STRAIGHT FACTS. Sometimes distorted truths or twisted lies partially belie the evidence in plain view.

      The accuracy of TRUTH has been determined to suffer a truth variance. Politicians are known to spin yarn and alter the very fabric of space, time, and facts usually accepted without question. However, due to their dragging the truth so far as to rip the facts from the framework, the results are about only 10% accurate.

      There is a margin of error of this report of about 4.8992.2333.285%

      This truth is NOT to be tisdorted, nor dispooted.

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    8. Re:Don't Get TOO Excited by Crayon+Kid · · Score: 1

      Should all the money have been spent on Gravity Probe B to prove something everyone accepts, or should other ways (like digging up 11 years of satellite data) have been used and the money spent on something that might actually give a bang for the buck?

      I think a "definitive", fancy and high-cost experiment where all the considerents have been included is useful to put this issue aside once and for all. No matter how "sure" one may be about frame dragging being true, it helps to actually prove it with a lot of precision.

      --
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    9. Re:Don't Get TOO Excited by fatphil · · Score: 2, Insightful

      No amount of precision will _prove_ the correctness of a theory. It will _support_, but not prove.

      Theory - All pigeons are grey.
      No number of grey pigeons can prove that theory true as if after that number of grey pigeons has been found an albino one is seen, then the theory is disproved.

      Anything which can be later disproved can not have previously be said to be proved.

      FP.

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    10. Re:Don't Get TOO Excited by Anonymous Coward · · Score: 0
      fashion. But there's no way that frame dragging could be the place where General Relativity gives out. It's an experiment that needed to be done. It's dotting the i and crossing the t. But it's not worth much. That's the real debate. Should all the money have been spent on Gravity Probe B to prove something everyone accepts, or should other ways (like digging up 11 years of satellite data) have been used and the money spent on something that might actually give a bang for the buck?


      Well, there are alternative theories of gravity, basically souped-up versions of GR, and they predict different amount of frame-dragging. So far all measurements that have been done have pointed to plain-ol' GR as being the correct theory, and no one expects frame-dragging to be any different, but it might be. Of course, the experiment is so darn delicate that if it measures anything but exactly what GR predicts, no one will believe it (but it would certainly stimulate additional experiments to settle the matter).

      As an aside, the people who did this experiment have shown that if you could only put up another LAGEOS satellite in a specific orbit (essentially with an inclination 180 degrees minus the inclination of another satellite), then the effects from the Earth's multipole moments would cancel out (i.e. we would not have to rely on an accurate Earth map and a ton of analysis). Since the LAGEOS satellites are little more than mirror balls, it would be pretty cheap to do this (at least, in comparison to GPB).
    11. Re:Don't Get TOO Excited by ByteSlicer · · Score: 1

      Should all the money have been spent on Gravity Probe B to prove something everyone accepts [...]

      The Gravity Probe B experiment was the only way to directly measure the effects of frame dragging. The other measurements so far all used indirect effects or included too many other uncertainties. So yes, it was needed. Also, a lot of the research results from that 11 year period were already incorporated into other satellites (e.g. cooling of IR satellite sensors), even before they were used in GPB. So the money was not just 'wasted' on GPB, but created a lot of new and practical knowledge.

    12. Re:Don't Get TOO Excited by Kombat · · Score: 1

      Theory - All pigeons are grey.
      No number of grey pigeons can prove that theory true


      You need to take a logic course, as this is not what is being argued here. Your example could be extended to "prove" that gravity is not proven. Although every massive body we've observed exhibits gravity, you claim that this doesn't prove gravity exists, since there could theoretically be a massive body out there without gravity.

      So what, we should question gravity now?

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    13. Re:Don't Get TOO Excited by Anonymous Coward · · Score: 0
      How about when that number is equal to the total number of pigeons?

      How about when you define pigeon to only be grey?

    14. Re:Don't Get TOO Excited by cHiphead · · Score: 1

      True, but its always exciting to learn that maybe, just maybe, we can toggle clipping on and off. now we just have to figure out how to get god mode in case we walk through a wall/dimension and into a cyberdemon.

      cheers.

      --

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    15. Re:Don't Get TOO Excited by fatphil · · Score: 1

      Gravity isn't proven in the same way as conservation of mass wasn't proven.

      Presently it's only an _assumption_ that inertial mass is the same as gravitational mass. That it was an assumption was made _explicit_ to us in college. Perhaps your lectures were dumbed down a bit. We have no reason to doubt it, and therefore it's as much a postulate as anything else is in the system.

      We simply have a model, which is less wrong[*] than our previous model. Prior models had as laws things like conservation of mass, which we now know to be false due to mass/energy equivalence. Prior models had ultraviolet catastrophies. Prior models had electrons as distinct particles. Prior models had no Lorenzian invariant transformations.
      Prior models had no Pauli exclusion principle. Prior models had no uncertainty principle.

      Stop thinking that our current model is unassailable.

      There are still unencountered, and thus untested, situations where our model could easily break down. C.f. the loss-of-information question categorically _not_ resolved recently.

      FP.
      * - Stephen Hawking's words, not mine.

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    16. Re:Don't Get TOO Excited by Retric · · Score: 1

      Yes, you should question gravity.

      Perhaps not as much as say the latest new idea in string theory but you should still question it to some degree. Science is a house of cards built on a bead of sand once you stop calling something a theory you enter the realm of faith.

  7. I don't know if you noticed.... by temojen · · Score: 1, Troll

    Slashdot only has links to news stories... in this case to CNN.

    1. Re:I don't know if you noticed.... by Anonymous Coward · · Score: 0

      Don't know if you noticed, but slashdot isn't a news provider, it's a news discussion facilitator.

    2. Re:I don't know if you noticed.... by PriceIke · · Score: 1

      One could say the same about CNN.

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  8. Isn't it time soon... by themadphysicist · · Score: 3, Insightful

    ...to change from 'theory' it to The Laws Of Relativity?

    1. Re:Isn't it time soon... by ZorbaTHut · · Score: 3, Insightful

      No. Not until it's proven. As long as someone could come up with another theory that predicts the exact same results, in a different way, which is not disproven, it's still a theory.

      For example, I could say "My theory includes everything in General Relativity, except for a small sphere four miles wide in the center of Andromeda, where light travels twice as fast."

      Yes, this makes truly proving anything in the physical world basically impossible.

      --
      Breaking Into the Industry - A development log about starting a game studio.
    2. Re:Isn't it time soon... by Pugio · · Score: 1

      Do you even know what a theory is??? You can't make it a law. There are waaaayyy to many factors involved. A law is absolute - this is how something works. A theory is a set of ways to describe certain phenomena. There are still many many many predictions that must be proved before one could even BEGIN to think that it might be a Law (if ever).

    3. Re:Isn't it time soon... by mjm1231 · · Score: 4, Informative
      No. This is a common misconception, but theories do not become laws by collecting evidence in their favor. (Otherwise evolution would have been elevated from theory to law long ago). See this Wikipedia article.

      Actually, the article could do better to explain the difference between the law of gravity (which is the mathematical formula which describes the attraction between two masses) and the theory of gravity, which attempts to explain how or why two masses attract each other exactly that way.

      --
      Ideology: A tool used primarily to avoid the bother of thinking.
    4. Re:Isn't it time soon... by metlin · · Score: 1

      NO! Are you out of your mind?

      A law is essentially an axiom, and GR is not yet.

      Atleast not until all aspects and effects of it are proven completely.

    5. Re:Isn't it time soon... by Anonymous Coward · · Score: 0

      "There are waaaayyy to many factors involved. A law is absolute - this is how something works"

      We still refer to Newtownian gravity, as "the law" of gravity.

    6. Re:Isn't it time soon... by Olathe · · Score: 1

      Theory is a set of theorems. Anything that is a theorem is logically rock solid, as long as the axioms hold. The axioms of relativity already are laws.

      Law doesn't mean 'true', it means 'logical basis'. Theory doesn't mean 'well-accepted hypothesis', it means 'ideas that are correct if the laws are'.

    7. Re:Isn't it time soon... by the_mad_poster · · Score: 4, Insightful

      The easiest way to think of the distinction is that a theory is a set of calculations and observations that are used to explain some previously unexplained phenomena.

      A law, however, is something that is quite set in stone. In your example, you're actually referring to a set of equations that Newton put forth. These equations are quite absolute and will always reproduce the same output no matter how often a given set of variables is retested.

      Therefore, while a theory is a "best effort" explanation that tries to predict results, a law is a logical system (such as an equation) that must and will always produce the expected results given a defined starting point.

      --
      Alito: A vote for Alito is a punch in the eye to put that bitch back in her place!
    8. Re:Isn't it time soon... by Lord+Kano · · Score: 0

      ...to change from 'theory' it to The Laws Of Relativity?

      No. Because General and Special Relativity don't work at extremely small scales. That's why Quantum Mechanics exists. Relativity will never be a law because it's been observed to not work in some cases. The "Unified Theory" that someone eventually may develop could go on to be a law, but not Relativity.

      LK

      --
      "Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
    9. Re:Isn't it time soon... by Anonymous Coward · · Score: 0

      I too think the article would be much improved by your suggestions. It's the wikipedia - why don't you go an make those changes.

    10. Re:Isn't it time soon... by nerdguy569 · · Score: 1

      sorry, but special relativity is an integral part of quantum mechanics, Dirac integrated it within a couple of years of it being proposed. Hence, Special Relativity does work. the problem is General Relativity. if you want to have a good reason for not making special relativity a law, its the fact that its only applicable to inertial reference frames. General Relativity is going to fail someday so that a quantum theory of gravity and acceleration can take over, ergo, we do not have a law of relativity, but theories, one which is true for all inertial frames, and one which is applicable to all classical frames of reference.

      --
      In the future, we will all be very smart or very stupid.
    11. Re:Isn't it time soon... by greg_barton · · Score: 1

      Yes, this makes truly proving anything in the physical world basically impossible.

      And this is why theories are judged not just on the hypotheses (predictions) they create, but the testability of these hypotheses.

    12. Re:Isn't it time soon... by 3Bees · · Score: 1

      The best explanation of the difference between 'theory' and 'law' that I have heard is: Laws describe, theories explain.

      --
      "I think we should tax people who stand in water! " - Mr. Gumby
    13. Re:Isn't it time soon... by anethema · · Score: 1

      Isnt the first thing most people are taught in general science class in high school is that a theory can NEVER be proven, only disproven.

      A theory might seem very sound untill some phonomina coomes along that doesnt fit..then we make another theory.

      When a theory has tested well against anything we could throw at it, it becomes a law.

      Law of thermodynamics..ohms law..etc.

      --


      It's easier to fight for one's principles than to live up to them.
    14. Re:Isn't it time soon... by king-manic · · Score: 3, Insightful

      It's more splitting hairs then anything. A law or a theory doesn't have a official test for one to graduate to the other. The "law" of gravity is wrong in most cases due to quantum effects in large scale or minute scales. It's more about tradition then it is about classification.

      --
      "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
    15. Re:Isn't it time soon... by 01D* · · Score: 1

      Yes, this makes truly proving anything in the physical world basically impossible.

      There's a small contraption to help humanity deal with the situation, it's called Occam's Razor

    16. Re:Isn't it time soon... by astroboscope · · Score: 1
      While agree with other posters in this thread about the difference between laws and a theory, I'm guessing you were trying to get at something else: practically, how much experimentation is needed to verify a theory?

      I don't know, but for GR I see 2.5 reasons to keep experimenting:

      • GR, and even special relativity to some extent, appears to not be fully consistent with quantum mechanics (QM), another theory that is very well supported by measurements. Therefore it is natural to expect that at least one of them will need modification.
      • Yes, there are some theories that try to unify them, but they are much more tentative (i.e. need experimental support or disproval). Small deviations from either GR or QM would be a Big Clue, but of course it's not automatic that Gravity Probe B in particular was worth $700M.
      • Gravitational waves are billed as another as yet unverified prediction of GR, but
        • A Nobel prize was given years ago for their detection in a pulsar system.
        • Far more importantly, they are astronomically interesting more or less independently of GR.
      Whether Gravity Probe B was worth $700M, assuming they don't get lucky and find something, depends on few things:
      1. Do any of the hot theories really care about frame dragging, or do they all agree on it anyway? I have not seen a lot of controversy about this.
      2. Was the time (4 decades?!) and money really needed when 2 separate experiments have found it in the last 2 years? Clifford Will's complaint that the Italian result might be thrown off by the Earth's inhomogeneities falls flat when the number is so close to the Lense-Thirring prediction. That'd be quite a coincidence (but not earth shatteringly so). When the discrepancy is only 0.1 standard deviations, it's more likely that the uncertainties were overestimated than underestimated. Of course the Italians knew what number to shoot for, but if you're going to examine motivations you may well consider that Will likes testing GR to high accuracy, so of course he'd like to see Gravity Probe B go on to measure frame dragging to within 1%. And on that he's right - it's up there now, so we might as well see what it has to say.
      --
      If we were ants living on a Rubik's cube, differential geometry would be a little more confusing.
    17. Re:Isn't it time soon... by dasunt · · Score: 2, Insightful

      No. Not until it's proven. As long as someone could come up with another theory that predicts the exact same results, in a different way, which is not disproven, it's still a theory.

      For example, I could say "My theory includes everything in General Relativity, except for a small sphere four miles wide in the center of Andromeda, where light travels twice as fast."

      You joke, but interestingly enough, something like that has happened. Newton came up with a set of "laws" for the physical universe, and that set of laws worked out remarkably well, until back in the 1900s, the planet Mercury's observed position was different from where it should have been.

      Many people were searching for a tenth planet between Mercury and the sun (planet Vulcan), until Einstein came along with relativity and showed why we weren't seeing Mercury in the right spot.

      Now, for many, many common tasks, Newtonian physics works just fine. An engineer will use it every day for the rest of his life without having any problems.

      But for very precise measurements, extremely high speeds, extremely large masses, etc, Newtonian physics will give the wrong answer.

      In short, Newtonian physics acts like a subset of Relativity.

    18. Re:Isn't it time soon... by Man+In+Black · · Score: 1

      A law, however, is something that is quite set in stone. In your example, you're actually referring to a set of equations that Newton put forth. These equations are quite absolute and will always reproduce the same output no matter how often a given set of variables is retested.

      Well, no, not really... Newton's "Laws" don't apply at relativistic speeds. That's why we have relativity. The only reason we still call them "Newton's Laws" is due to tradition. If the same scientific rigor, dogma, and beuraucracy was around in Newton's times, they probably wouldn't have called them "Laws" in the first place.

      It would be short-sighted to assume that simply because we have more proof of frame dragging that relativity has been "proven" and should be considered a "law". Indeed, there are almost certainly extreme cases (which we have yet to encounter or even predict) where relativity ceases to provide adequate results, just like how Newton fails to provide adequate results at extremely high speeds. Does relativity still hold at the center of a black hole? Did it hold during the early stages of the universes creation? The fact is that every new theory is just an attempt to get more and more accurate results by taking into account new extreme possibilities as we come to realize them. We started off with Newton, relativity built on that, quantum mechanics built on relativity, and perhaps in the future we will be able to say that string theory built on quantum mechanics. We'll never really be able to say that we know something absolutely because we will never be sure that there aren't some odd set of extreme circumstances that cause things to work differently. And if you think that we'll never find such extreme circumstances, then go back in time and try to explain to Newton why time dilates just because you're travelling really fast.

      Of course, the whole discussion is rather foolish.... in the end, it doesn't really matter whether we call it a "law" or a "theory". Even when we do inevitably find a case where relativity ceases to apply, it will still be used for more mundane cases just like the way we still use Newton's laws for mundane cases that don't require the extra precision of relativity. Even when we do manage to prove that it's not absolute, it's already proven that it's useful at the very least.

      --
      -"One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man." -EH
    19. Re:Isn't it time soon... by servognome · · Score: 1

      There's a small contraption to help humanity deal with the situation, it's called Occam's Razor
      There's also a small contraption called statistics, which tells us our data set is too small to really understand what goes on in the universe.
      If you applied Occam's Razor to the patchwork of science you would decide to throw everything out the window. We have decided that certain theories are "good enough" for now until we can come up with something better.

      --
      D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
    20. Re:Isn't it time soon... by Anonymous Coward · · Score: 0
      If you applied Occam's Razor to the patchwork of science you would decide to throw everything out the window.
      Damn straight. Me and the other Flat Earthers are having a meeting tomorrow. Everyone's invited. We'll have punch 'n pie!
    21. Re:Isn't it time soon... by J.R.+Random · · Score: 1
      ...to change from 'theory' it to The Laws Of Relativity?
      The problem is that you're using the laymen's notion of "theory", which roughly means "a tentative guess". But that's not how scientists use the word. A theory is simply a proposed set of relations among observables, and its status may range from rampant speculation to solidly established fact. After all mathematicians talk about "Group Theory" and "Number Theory", when there's nothing tentative about, say, the prime number theorem.
    22. Re:Isn't it time soon... by Anonymous Coward · · Score: 0

      with all this talk about splitting hairs i thought i should mention that...

      THEN != THAN!!!!!!!!!!!!!

    23. Re:Isn't it time soon... by 01D* · · Score: 1

      occam's razor is quite naturally integrated with statistics:
      Assume you have a family of models with different number of descriptive parameters: n
      Now building the posterior p(n| {observation}) and maximizing it with respect to n, you get Occam's Razor in action -- you actually HAVE to pick a model which both describes the available data (scarsity of it is irrelevant) as well as doesn't overfit it by introducing extra (unnecessary) parameters.
      This certainly dis-glorifies philosophy of science since it makes a "principle" a mere technicality, but it's your choice to face the facts(using the statistics that you refer to) or continue speculations.
      Check this out: http://www.amazon.com/exec/obidos/tg/detail/-/0198 518897/

  9. Re:CNN beat you to this punch by ikkonoishi · · Score: 1

    RTFA

    It links to the cnn article...

  10. Re:CNN beat you to this punch by the_mad_poster · · Score: 3, Informative

    The original linked article IS CNN's writeup. Read the Nature article. CNN may have beat them to the punch, but there's some question as to the accuracy of these findings that CNN conveniently didn't mention.

    --
    Alito: A vote for Alito is a punch in the eye to put that bitch back in her place!
  11. Time travel by temojen · · Score: 0, Offtopic

    Is not far behind...

    1. Re:Time travel by Short+Circuit · · Score: 1

      Thinking of time travel...anyone know of a place where I could debate things like the effects, or even the possibility, of going back in time and eliminating an ancestor before they procreate?

      It's a fun topic to debate.

    2. Re:Time travel by Boyceterous · · Score: 1

      Time travel is *never* behind!

    3. Re:Time travel by Tumbleweed · · Score: 2, Funny

      Your local junior high science fiction club would be a good place.

    4. Re:Time travel by Fortran+IV · · Score: 1

      Don't forget Larry Niven's Rotating Cylinders and the Possibility of Global Causality Violation, a suggestion that the universe may defend cause-and-effect quite violently. Attempting to change the past might lead to a sudden alteration of your present.

      --
      I figure by 2030 or so my 6-digit UID will be something to brag about.
    5. Re:Time travel by Olathe · · Score: 5, Insightful

      If backward time travel is possible, it does not seem it would have any adverse effects. Physics does not care about your lineage. Assuming you shot your ancestor, the bullet would not mystically stop and the particles that make up your body would not mystically disappear.

      It does not matter that you would not be born to go back in time. Physics does not care about you as a being. If your particles exist in a certain configuration at a certain time in the past, it does not matter that the original cause no longer exists. Physics does not care about timelines. It only cares about the instant immediately preceding the event. Only people care about unbroken chains of cause and effect, not physics.

      All the confusion comes from people creating paradoxes by ignoring deterministic physics laws and imposing stupid irrelevancies.

    6. Re:Time travel by Olathe · · Score: 2, Insightful

      I already stated that. Physics is deterministic. It does not care about nice, logical, unbroken chains of cause and effect. All it cares about is taking the snapshot at one instant to transform it into the snapshot at the next instant.

      Most theories with paradoxes are based on the idea that the universe will suddenly act strangely because it somehow notices there is no longer a cause for the particles to be in the place where they are now. Again, the universe does not care about cause, it's mechanistic (and a bit probablistic, but this doesn't harm my argument) and only does its job.

      In a computer analogy, assume you have a computer in which one process starts another. You can travel back in time, and you flip the bits to make the child program execute at an earlier time. It terminates the parent program before the program is called. The child program doesn't suddenly stop. The computer, being mechanistic, does not care that it no longer has a cause.

    7. Re:Time travel by Creepy+Crawler · · Score: 2, Interesting

      Bzzt, wrong.

      If the whole idea of superstrings and 10-N dimensions are correct, then there are an infinite universes. The superset of these universes would include every possible random quantum event, and every effect from each.

      In order to travel from one time to "another", you actually would guide to a universe very close to your diversion rate. You could kill off everybody, and it wont effect you at all. Then again, returning back to "your" time is impossible, as you can only approach your universe as a infinite limit (yeah, fun).

      --
    8. Re:Time travel by Anonymous Coward · · Score: 0

      Sometimes I feel like a motherless child.

    9. Re:Time travel by Anonymous Coward · · Score: 0

      Uh, superstring theory does not necessitate multiple universes. (It can accomodate them, depending on what your definition of "universe" is, but does not require them.)

      It sounds like you're just garbling the so-called "many worlds" interpretation of quantum mechanics. (QM, by the way, doesn't necessitate this interpretation or the idea of multiple universes, either.)

    10. Re:Time travel by Anonymous Coward · · Score: 0

      That wasn't Larry Niven (SF author), that was Frank J. Tipler (mathematician).

    11. Re:Time travel by nerdguy569 · · Score: 1
      In a computer analogy, assume you have a computer in which one process starts another. You can travel back in time, and you flip the bits to make the child program execute at an earlier time. It terminates the parent program before the program is called. The child program doesn't suddenly stop. The computer, being mechanistic, does not care that it no longer has a cause.
      hate to tell you, but you changed the program already so that the child is already running, this analogy doesn't apply. the grandfather paradox has been contemplated for centuries, and no one has invalidated it so far, the only interpretation of current physics which eliminates thes paradoxes is the multi-universe interpretation, which says that every time a probabalistic event takes place that universe splits into a universe with each possible outcome, and also, if one goes back in time, they effectively enter another one of those universes. and therefore will not affect their own universe, preventing themselves from threatening their own existence.
      --
      In the future, we will all be very smart or very stupid.
    12. Re:Time travel by Anonymous Coward · · Score: 0

      so much for back to the future flicks :/

    13. Re:Time travel by 808140 · · Score: 3, Informative

      You're missing the OP's point. His computer analogy obviously doesn't hold literally; he's trying to explain that causality doesn't have much sway in Modern Physics. While we may be unable to send our entire bodies back in time, particles do it essentially all the time. It seems as though our current understanding of physics (both on the macroscopic general relativity scale and on the microscopic quantum scale) not only allows but actually encourages this kind of bizarre behaviour.

      The confusion comes from classical mechanics, where we typically would model real-world behaviour parametrically -- and time was the parameter. So for example, we would explain the movement of a particle as vector function of time. This works fine, most of the time. But it isn't general enough.

      Relativity showed that time is not a parameter anymore than classical dimensions could be considered a parameter, it's just that we perceive it that way. Time is actually a quantity much like space. It doesn't behave exactly the same way, but that's a result of the metric of the spacetime continuum (see Lorentz transforms in Special Relativity for an example of this).

      So, now we have a particle occupying a position (x,y,z,t) instead of occupying a position (x,y,z) at a particular time t. In the same way that we accept that a particle can retrace its path when moving along the x axis, we must accept that a particle can move backwards on the t axis (it just isn't thermodynamically efficient to do so).

      Let's talk about you and your grandfather. Your grandfather is at point (x,y,z,t) and you are at point (x',y',z',t'), presumably with t' > t. You time travel back to time t, and kill him. He ceases to exist at (x,y,z,t).

      Now, because time is a positional coordinate, if you will, and not a parameter, you have not "arrested his movement". People like to wrap their heads around this by imagining that in changing the past you have "forked" the universe and that this new forked version will never produce you, but you aren't destroyed because you come from a different version of the future.

      The point is that physics doesn't care why you came into being, only that you came into being. You exist; you will not cease to exist just because the thing that "created" you was destroyed. This leads philosophers to suggest that everything exists inherently, and that we just pick our way through a myriad of decision universes. It's a way of making our logic apply to physics. At the moment there's no evidence for it.

      The "kill your grandpa" paradox was used in the old days to explain why time travel was impossible; and yet time travel is manifestly possible, even if harnessing it poses an engineering problem. It happens at the particle level all the time (positrons are electrons moving backwards in time, says Feynman). This suggests, then, that our starting principle is flawed (reducto ad absurdum). The "fall guy" in this case is causality. Causality doesn't matter. We hold on to it because we have memory. But cause can follow effect, etc... I mean, it's a bizarre world we live in.

    14. Re:Time travel by Olathe · · Score: 1

      Hate to tell you, but that's exactly why it does apply.

      You changed the space that was previously empty to contain a fully functional human being. That's the essence of time travel. This is directly analogous to changing the previously unused memory of a computer system to contain a fully functional child program.

      The strength of your argument rests on how long a lot of people have believed something. This is not a foundation at all, let alone a strong one, against a new argument. If the universe is indeed mechanistic, deterministic, and iterative, there is no valid conclusion but the one I made.

      The strongest argument I know of against the standard reasoning is that it is based on assuming that there is only one timeline (or many with multiple universes) that is fixed after it is traversed. My point of view is that timelines are an abstraction that makes some things easier to think about, but only serves to confuse people here.

      There is no reason to think that timelines actually exist. There are only matter and energy in their own present time and location. If a human travels back in time and murders his parent, it does not shatter a timeline and thus lead to logical inconsistencies. It only causes a rearrangement of matter and energy no different from the quadrillions that are happening all around it.

      Assuming the reality of one or more timelines leads to logical contradictions or paradoxes. Assuming that they don't really exist, but are merely aids to thinking leads to no logical contradictions or paradoxes. I don't see a good defense of the standard view.

    15. Re:Time travel by AlexV · · Score: 1

      It seems to me that the only problems with time travel paradoxes are semantic, specifically with what you mean by "changing" things. To change something (like whether your ancestor is alive or dead), this is a difference in states over a period of time (alive at time t, dead at time t+1), where t is an arbitrary time, like 11.30am on 23rd November 1987.

      If you allow that time travel is possible, you are just shifting your x,y,z,t co-ordinates, so there is now an entity "Alex" at 11.30am, 23rd November 1987. But this simply means that this entity exists then. The change is that there wasn't one at 11.29, and that there is one at 11.30, not that there wasn't one at some 'previous' 11.30 and you have changed it so that there is one now - this makes no sense.

      There can be no paradox, it is simply extremely unlikely that you shot your father. While I guess we can't completely discount acausal creation of a human being, it doesn't seem likely. Far more likely that you simply didn't shoot your father. Depending on what time co-ordinate you put your viewpoint at when describing the event you either:

      Will not shoot your father
      Did not shoot your father
      Are not shooting your father.

      This may have disturbing consequences for those who like to believe in their free will to influence their environment, but don't worry about it. As long as you don't know what happens at time t+1 you can assume you can 'change' it, however meaningless this statement might be!

    16. Re:Time travel by Anonymous Coward · · Score: 0

      the assorted sci.physics newsgroups is a good place to debate this stuff...

      There are some real cranks so it's good value for time spent from an entertainment angle too. If unfamiliar, use google to dig up "archimedes plutonium" for starters.

      physics guys...
      what sort of periodicity function is predicted for gravity waves?

    17. Re:Time travel by Sgt_Jake · · Score: 1

      so... what your saying is... I can drink the same 6 pack OVER AND OVER?! Time-space rocks...

    18. Re:Time travel by wjwlsn · · Score: 1

      A nice article on retro-causation:

      http://plato.stanford.edu/entries/causation-backwa rds/

      --
      Getting tired of Slashdot... moving to Usenet comp.misc for a while.
    19. Re:Time travel by Fortran+IV · · Score: 1

      In his collection Convergent Series, Niven introduces the story in question with two lines:

      This story has a catchy title. I stole it from a mathematics paper by Frank J. Tipler.
      --
      I figure by 2030 or so my 6-digit UID will be something to brag about.
  12. Not Very Accurate by Fareq · · Score: 1

    Either way, the Gravity Probe B experiment is expected to deliver a measurement of frame-dragging with 1% accuracy very soon.

    Hmm... I don't know that results that are only 1% accurate are particularly meaningful in any measurement or experiment. I assume that they actually meant accurate to within 1% but that would be 99% accurate...

    Or am I completely missing the obvious again...

    1. Re:Not Very Accurate by vondo · · Score: 1, Informative

      "with 1% accuracy" is perfectly acceptable. If you have a meter stick that you can measure the length of something "with 1 mm accuracy," that's what you're interested in. The statement you quote means Gravity Probe B will be able to measure with an accuracy of 1% of the predicted value.

    2. Re:Not Very Accurate by Short+Circuit · · Score: 1

      Pedantic:

      Er...you mean "actual value," since it's not a given that the actual value and predicted value will be the same.

    3. Re:Not Very Accurate by vondo · · Score: 1
      No I don't. The predicted value is known. The actual value isn't. So you can't know what percentage of the actual value the accuracy will be.

      This of it this way: if the actual value is 0.00, then by your definition, the probe will make a perfect measurement.

    4. Re:Not Very Accurate by rgarcia · · Score: 2, Informative

      Plus, they say that the drag is about 6 feet or 2 meters? Not quite. I must nitpick.
      2 meters is about 6'7", or 6 feet is about 1.82 meters. So which is it?

      The metric system strikes again, I guess.

      --

      I couldn't fail to disagree with you less.

    5. Re:Not Very Accurate by Short+Circuit · · Score: 1

      You said they were measuring the "predicted value" ... you don't measure predicted values. You take measurements, and compare them to predicted values. The predicted values are known before hand; they're theoretical.

      Sorry. /pedantic

    6. Re:Not Very Accurate by vondo · · Score: 1

      I said: to measure with an accuracy of 1% of the predicted value. which is not the same as saying they are measuring the predicted value. After "measure" there is an implied "(the actual value)"

    7. Re:Not Very Accurate by Anonymous Coward · · Score: 0

      Don't you mean to within 1 cm?

    8. Re:Not Very Accurate by Mr.+Slippery · · Score: 1
      6 feet is about 1.82 meters. So which is it?

      With only one significant digit - as given in the article - 2 meters converts to 6 feet. (It didn't say "2.0 meters", right?)

      And at three significant digits, it's closer to 1.83 meters than 1.82. (There are 2.54 cm/inch by defintion, so the conversion is precisely, 1.8288 m.)

      <curmudgeon>Don't they teach you kids these days about significant digits and rounding? Why, back in my day...</curmudgeon>

      --
      Tom Swiss | the infamous tms | my blog
      You cannot wash away blood with blood
    9. Re:Not Very Accurate by Sparr0 · · Score: 1

      6'7" is 109.722% of 6'. Which puts either answer within the 10% margin of error :-p

    10. Re:Not Very Accurate by Anonymous Coward · · Score: 0

      just to clarify the metric system:
      1mm is 0.1% of a meter. 1cm is 1% of a meter.

    11. Re:Not Very Accurate by wattersa · · Score: 1

      or rather, if 1% is the standard error of the mean, and (e.g.) the mean observed value is 100, we can be 68% certain that the true value is between 99 and 101-- one standard error. We can be 95% certain that the value is between 98 and 102-- two standard errors. And 99.7% certain that the value is between 97 and 103-- three standard errors. The article wasn't clear on whether the probe measures within 1% of the theorized value or whether it has a 1% standard error for measuring the observed value :-/

    12. Re:Not Very Accurate by Infinityis · · Score: 0

      Well, all I know is that the results as presented seem a bit misleading. I mean, it obviously can't be 109% accurate, and it can be a low as 89% accurate. Thus, given an upper limit of 100% accuracy, shouldn't they be saying 94.5% accurate to within 5.5%?

    13. Re:Not Very Accurate by mollymoo · · Score: 1
      Plus, they say that the drag is about 6 feet or 2 meters? Not quite. I must nitpick. 2 meters is about 6'7", or 6 feet is about 1.82 meters. So which is it?

      Both. 6 feet is about 2 metres which is about what they measured.

      --
      Chernobyl 'not a wildlife haven' - BBC News
  13. Comment removed by account_deleted · · Score: 5, Funny

    Comment removed based on user account deletion

  14. This project was batshit nuts by Anonymous Coward · · Score: 3, Informative

    Read up the history of this project sometime. This is the longest running single project in the history of the federal government, it took like 50 years to complete because they kept getting stalled and most of the work was being done by grad students. In order to do this experiment they had to build what are, more likely than not, the two most perfectly round objects in the entire universe and then spinning them really really really quickly in a vacuum in outer space.

    Crazy shit.

    1. Re:This project was batshit nuts by Scott+Ransom · · Score: 3, Interesting
      In order to do this experiment they had to build what are, more likely than not, the two most perfectly round objects in the entire universe...

      Actually, they are only the most spherical things in our little region of the galaxy. Neutron stars (of which the closest known is a couple hundred lt-yrs away) are even more spherical.

      And yes, IAAA (I am an astronomer).
    2. Re:This project was batshit nuts by martinX · · Score: 1

      This project was batshit nuts

      I think that very phrase will appear in the abstract.

      --
      When they came for the communists, I said "He's next door. Take him away. Goddam commies."
    3. Re:This project was batshit nuts by Caraig · · Score: 3, Interesting

      Wouldn't a neutron star be spinning at tremendous angular velocities, and therefore be deformed along its equator, forming more of a flattened sphere shape? Heck, even spinning at any velocity, it sould deform along the equator. Or am I missing something about neutron stars?

      --
      "I am an Adept of Tantric VAX."
    4. Re:This project was batshit nuts by ElAurian · · Score: 1

      Aren't neutron stars usually oblate spheroids, because of their huge spin?

    5. Re:This project was batshit nuts by mikael · · Score: 1

      Wouldn't a neutron star be spinning at tremendous angular velocities, and therefore be deformed along its equator, forming more of a flattened sphere shape?

      You are forgetting the intense force of gravity for a star that dense. The force of gravity at the surface of our sun is around 1000G (10,000 metres/second per second). The force of gravity for a neutron star is thousands of times greater than this. If a neutron star has an atmosphere it's no more 5 millimetres deep, with any variation in height compressed to less than two millimetres or less. Scientists are able to measure "starquakes" on these objects due to the variations in their brightness.

      --
      Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
    6. Re:This project was batshit nuts by PSUspud · · Score: 1

      Yep, you're absolutely right. In grad school, I went to a colloquium where the speaker made just that point, and then illustrated it with a spinning water balloon. Some pretty neat stuff can come out of spherical harmonics -- try it sometime.

      Oh, there are a bunch of uncertainties here. First, the equation of state (relationship between pressure and density) is unknown, so we can't model the exact behaviour. Second, while we can guess that the neutron star is a superfluid (zero viscosity), it hasn't been verified experimentally (Nobel prize for first trip to a neutron star!). So, in summary, this is a great area for speculation, all you gravity heads!

      --
      ----- Why sig when you can sign? PGP key id 7675D05E
    7. Re:This project was batshit nuts by Scott+Carnahan · · Score: 1

      Wouldn't a neutron star be spinning at tremendous angular velocities...

      You may be thinking of millisecond pulsars. Not all neutron stars spin at high angular velocities, and the slow ones have very little deviation from a ball shape.

      --
      "Your notation sucks!" -- Serge Lang (1927-2005)
  15. No, you're wrong. by Anonymous Coward · · Score: 5, Informative

    You're thinking of NASA's Gravity Probe B. That one isn't finished yet.

  16. Some Equations by nate+nice · · Score: 4, Funny

    Tysons Equation explains this:

    ch/(c - ke^n)

    Where c is speed of light, of course, h is a coefficient representing the fabric and this is a quotient where k is a coefficient to the constant e (~ 2.7) and raised to n which is a variable for mass or changing objects in space.

    Sanders developed a corollary for this saying:

    f-r/e^d

    where f is the temperature in space in farenheight and r is the change, divided by e, again, to the d, which is similar to n, but loses its delta value.

    It's a lot to grasp if you don't know physics well, but what they say is that objects do indeed get entangled in the fabric of space time and move, due to gravity. Neat stuff...really. Hehehe.

    --
    "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
    1. Re:Some Equations by JAgostoni · · Score: 1

      I think the fact that this is modded +Informative is damn hilarious. Almost as hilarous as Tyson Chicken and Sanders' Fried Chicken. Mmmm Chiiicken.

    2. Re:Some Equations by synaptik · · Score: 5, Funny

      Stupids mods... this should be funny, not informative. "Chicken" ... "Sanders" ... "Fred" ... it's obviously a joke.

      A real 'clucker' of a joke, in fact.

      Not posting anonymous, so that I can receive the karmic flogging I deserve for making this meta-comment.

      --
      HSJ$$*&#^!#+++ATH0
      NO CARRIER
    3. Re:Some Equations by metlin · · Score: 1

      Mr. Crusher, please get away from the chicken and eggs, and back to your books.

    4. Re:Some Equations by DeepFried · · Score: 0, Flamebait

      I'm suprised you forgot to mention the Taurus Theorum when citing Tyson.
      (BüLL)=[S/-/it]

      which as we all know is derived fromt he Malarkey Principle
      _[LoAd]= o£- K®@P

      I think people will look at your post and think "oooh math!" and continue mod you informative. Hacking human nature.

      --


      Who is General Failure, and why is he reading my hard disk?
    5. Re:Some Equations by ConceptJunkie · · Score: 3, Funny

      Sanders developed a corollary for this saying:

      f-r/e^d


      You were describing a formula developed by Gwynne(65) and further developed by Sanford(73), and Schneider(77).

      Sanders' Equation was:

      hAr/(l^An)

      where h is Planck's constant, A sub r is the acceleration frame relative to the rotating mass, l is the angular momentum, and A sub n is the acceleration frame normal.

      I understand this formula works for 11 dimensions (or "vibratory branes"... often referred to in terms of "hertz and spaces"), but no one besides Sanders seems to understand exactly what they are.

      Just like Relativity which has the Special and General versions, this also has two versions, related to General Relativity and M-theory respectively.

      These are commonly referred to Regular and Extra Stringy.

      --
      You are in a maze of twisty little passages, all alike.
    6. Re:Some Equations by nate+nice · · Score: 1

      Ah yes, the Taurus Theorem. I most definitely should have made note of it, but I assumed people would know to cite this. I guess I overestimated the intellectual might of this forum. To the study!

      --
      "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
    7. Re:Some Equations by nate+nice · · Score: 1

      "These are commonly referred to Regular and Extra Stringy."

      Those are cool and all but I've really been into "Nugget" theory, named after Shigaro Nuggs. Basically, it is based on A sub R sub h. This second derivative in the multi variable function explains how to decompose Tysons theorem into modular pieces that scientists can devour quickly spur research. The research looks promising, if only we could somehow integrate it with Maxwell's equation regarding proper heating for granular substances. Ahhh, we can dream.

      --
      "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
    8. Re:Some Equations by Anonymous Coward · · Score: 0


      Chew on this
      tr/den^t gives you wisdom and pure chewing satisfaction.

    9. Re:Some Equations by ConceptJunkie · · Score: 1

      The problem with the Nugget theory is that while it appeared to be a decomposition of Tyson's theorem, really it was patched together from by-products of disproved formulae and contained very little of Tyson's ideas.

      --
      You are in a maze of twisty little passages, all alike.
    10. Re:Some Equations by nate+nice · · Score: 1

      "...and contained very little of Tyson's ideas."

      Well, yes and no. That was really the point of it in the first place. It still uses much of the same process that Tysons does but found new approaches. Sure, some of it was *thought* to be disproved but McDonald proved it was a reality and went on to expand the theory into a more "tender" version, if you will. It's an easier concept to work with and just as valid.

      But, of course this is all very experimental, much like stringy theory (as it uses some of the vector equations of stringy), but definitely shows some promise. Only the future will tell, but I for one am a believer.

      --
      "If you are a dreamer, a wisher, a liar, A hope-er, a pray-er, a magic bean buyer ..."
    11. Re:Some Equations by theMerovingian · · Score: 1


      Sure, some of it was *thought* to be disproved but McDonald proved it was a reality

      Yes, I hear McDonald can be defensive about his work...

      --
      "If you think you have things under control, you're not going fast enough." --Mario Andretti
    12. Re:Some Equations by Airconditioning · · Score: 3, Insightful

      Maybe 'fried' instead?

    13. Re:Some Equations by Thunderstruck · · Score: 1

      The individuals who were responsible for this post have just been sacked!

      --
      Trying to use sarcasm in text-based forums does not work.
  17. Re:CNN beat you to this punch by nuclear305 · · Score: 2, Funny

    "lol.. kind of sad really.

    Read this hours ago on CNN, doesn't seem too interesting yet."


    Where did you think the submitter got the story, you insentive clod!

  18. More Info on twisting Space by alaivfc · · Score: 5, Informative

    This idea of this drag was originally proposed by Einstein. Almost fifty years ago, the idea of how to experimentally verify this effect was proposed; however, it required the launch of a very accurate gyroscope. That gyroscope, which is the center-piece of the longest running NASA project ever, was just recently launched into space. More info about it (Gravity Probe-B) and a good description of this drag can be found at http://einstein.stanford.edu. Yes, the article is describing a different project than GP-B; however, it references the skeptism that the folks at GP-B have expressed at this latest experiment, and the GP-B folks are considered the experts in the field. Check out their site, it's fascinating.

    1. Re:More Info on twisting Space by khallow · · Score: 1
      however, it references the skeptism that the folks at GP-B have expressed at this latest experiment, and the GP-B folks are considered the experts in the field.

      Healthy skeptism that would be expected from a rival that was "scooped". More interesting is that GP-B will get at least a factor of ten improvement over the current observations.

    2. Re:More Info on twisting Space by Darby · · Score: 1

      So can you give a reasonable laymans explanation of why it's even reasonable that the whole thing is true?

      I mean, it seems like it's similar to normal friction.

      Is this reasonable?
      Does that indicate that the "fabric" of spacetime is more like a real fabric than you might otherwise think?

    3. Re:More Info on twisting Space by Anonymous Coward · · Score: 0

      Yes, but this is as nothing compared to 'Gravity Probe-A'. The longest running project of the Royal Society ever, GP-A was begun 275 years ago in an attempt to attempt an experimental verification of Newton's Laws.

      Its design is quite ambitious, as it involves the construction of an artificial satellite one-fifth the mass of the Earth's moon. The launch of GP-A is planned to occur during the summer of 2150.

    4. Re:More Info on twisting Space by Anonymous Coward · · Score: 0

      Real fabric? I thought the "Yo Momma" joke thread was a couple pages up.

    5. Re:More Info on twisting Space by Anonymous Coward · · Score: 0

      Funny, but your in tough luck, GP-A was used for a probe on a ballistic trajectory and was equipped with a very accurate time piece, so as to find evidence for time dilation.

      Quickshot

    6. Re:More Info on twisting Space by Anonymous Coward · · Score: 0

      I'm not playing devil's advocate, but it would seem odd if a long-running, low-return (so far) $700M NASA-sponsored project DIDN'T doubt the validity of a simple, quick project using existing data that beat them to the punch. There's a hell of a lot of face to lose if they don't.

  19. That explains a lot... by Kjuib · · Score: 0

    That explains all the lag I have been getting on my online games...

    --
    - Your stupidity got you into this mess, why can't it get you out? -Will Rogers
  20. Perhaps by bleckywelcky · · Score: 5, Funny

    From the CNN article:

    "Ciufolini's team analyzed millions of laser signals bounced off two satellites, called LAGEOS and LAGEOS 2. Both are highly reflective spheres not designed to do any work of their own. They look like 2-foot-diameter (0.6m) golf balls and contain no batteries or electronics."

    Space Balls?

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

      --was photon pressure due to the "millions of laser signals bounced off of the two satellites" negligible, or taken into account?

    2. Re:Perhaps by Anonymous Coward · · Score: 0

      Space Balls the science kit? I'll stick with the flamethrower

  21. i don't understand this article by Trepidity · · Score: 4, Funny

    My framerate has been dragging too but I don't see the relevance of satellites to this issue. I've got cablemodem so satellite internet latency cannot be the problem.

    1. Re:i don't understand this article by carlmenezes · · Score: 1

      It's not a twist in the fabric of space. It's a hole in the canvas of windows.

      --
      Find a job you like and you will never work a day in your life.
  22. A Brief Explanation by Pugio · · Score: 5, Interesting
    For those who aren't familiar with all of this: (I know they included it in the article but here's my own explanation.)

    Basically (acc. to the theory of relativity), gravity is not really a pull from one object to the other. What it is is a distortion in the fabric of space-time. What does this mean? Well think about a sheet stretched out very flat. On this sheeta are a number of very light objects. Now think of a lead weight placed in the center of the sheet. The sheet will bend into an inverted cone shape and all the items will slide towards the weight. Ta Da! Gravity!

    Gravity is an extremely pervasive force. While it is the weakest of the defined forces, it permeates every area of our universe and, overall, has the largest impact. It is even powerfull enough to warp light. Again, just think of light as travelling along the surface of the sheet, the depression in the middle will warp the ligh as it travels.

    What this article is describing is a secondary gravitational effect. Now, not only does this lead weight cause things to fall towards it, but if the lead weight was spinning, it will create another path/pull of gravity. In the sheet example. think of the lead weight as shaped like a corkscrew. Now imagine what would happen if you started turning that corkscrew. Not only would the sheet be weighed down in that area but it would also become wrapped around the corkscrew, causing further twisting in the fabric of the sheet. This is the effect that is currently trying to be proved.

    Black holes are essentially very very very heavy weights. They create an extremely big "depression" in the fabric of the sheet. Many black holes also spin on their axis, much as the earth does. This spinning again distorts the sheet but, given how heavy the black hole is, it causes very large distortions.

    This is all predicted by the theory of relativity. For this theory to be considered valid, it must make certain predictions that can be (eventually) proven. If this experiment is, in fact, true then this is yet another proof that relativity is the real deal. And there you have it.

    Actually, now that I think about it. This pattern that they describe with the black hole looks exactly like a spiral galaxy (ie. the milky way) - with large "waves" coming out on all sides. It has been theorized that there is an enormous black hole at the center of the galaxy - could this be evidence of it?

    1. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      I find this stuff quite interesting. What I don't get is how you define something as rotating (and thus twisting spacetime)?

      Think of a satelite in geosync. orbit. According to its frame of reference, the Earth is stationary. Will it experience frame dragging - does the Earth's "corkscrew" twist spacetime(from its pov)? Does the rest of the universe "drag frames" instead?

      (IANAAP)

    2. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Law / Theory - i think you're getting the two confused. But a fair laymans explanation, regardless.

    3. Re:A Brief Explanation by OrangeGoo · · Score: 1

      I don't claim to be a physics expert, so forgive me if my question is stupid, but I am curious. From your example, the lead weight in the center of the sheet causes a depression in the sheet and the lighter objects move towards it because of the depression. If gravity fits the same description, then we're left without an explanation of why celestial bodies move towards each other. For example, a large planet (let's use Earth, though it isn't really large) and a moon sit in space. The planet causes a depression. Why would the moon move into the depression? Something must be pulling it down - the simple existence of a depression would not cause the moon to move (that is, if you reject gravity as the pull between bodies).

      As I said, I'm no physics expert. Your post just raised a question in my mind, and I figured I might as well ask it. :)

    4. Re:A Brief Explanation by Shelrem · · Score: 3, Insightful

      Disclaimer: i'm only the brother of an astrophysicist, and don't know much outside of what he's told me.

      The idea of independent frames of reference only holds for velocity. Rotation of an object involves acceleration towards the center of that object. Each point on a rotating circle moves tangentially to the circle, but that velocity is changed (accelerated) as it goes, because the tangent to the circle is different at each point it moves through. Thus, there is no rotating frame of reference for the earth.

      To test this idea in simpler terms: if you're in a zero gravity environment, and you're spinning, what happens when you pull your arms in? You start spinning faster, right (conservation of angular momentum and all that)? Well, if instead, you're stationary and the thing you're in starts spinning, what happens when you pull your arms in? Nothing! It's the rotating thing, not you, thus you have no angular momentum to conserve. If rotation was just another frame of reference, then to be consitant, when you pulled your arms in, the same thing would have to happen: the relative rotational speed would have to increase.

      Incidentally, that's also why we can definitely say that we orbit the sun, not the other way around.

      I hope that clears that up.

      b.c

    5. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      The rubber-sheet analogy only goes so far. In that analogy, objects move down the sheet because they're pulled down by an outside force (e.g. gravity). Of course, this is circular and makes no sense as a literal description of gravity itself. In reality, general relativity says that since gravity is the curvature of spacetime and not a force, objects under the influence of gravity alone will travel along straight lines -- just like Newton said. It's just that in curved spacetime, "straight lines" aren't the same as Euclidean lines. (e.g., a great circle arc on a sphere is a "straight line" -- or more technically, a geodesic -- on a curved surface.)

      Remember that this all happens in spacetime, not just space. For instance, an orbiting moon could not continuously go in a circle all the while rolling downhill in curved space. But it can do so by moving in a straight line in curved spacetime (in what turns out to be something like a helix shape).

    6. Re:A Brief Explanation by Pugio · · Score: 1
      From your example, the lead weight in the center of the sheet causes a depression in the sheet and the lighter objects move towards it because of the depression. If gravity fits the same description, then we're left without an explanation of why celestial bodies move towards each other. For example, a large planet (let's use Earth, though it isn't really large) and a moon sit in space. The planet causes a depression. Why would the moon move into the depression? Something must be pulling it down - the simple existence of a depression would not cause the moon to move (that is, if you reject gravity as the pull between bodies).

      The AC has a fair answer to this but I'll redefine it in slightly easier to understand language (at least, easier for me).

      For this example we need to think of time in concrete terms so... Think of the sheet example again. Now lets define the directions on this sheet. An object on this sheet can move forwards, backwards, left or right. Now let's say that when an object moves forwards or backwards it is actually moving forwards or backwards in time. An object moving left or right appears as physical movement to us. As time ticks by, the object is, by definition, moving forwards. Without any outside forces, this object will continue to move forwards in a straight line. Now consider that depression caused by the earth. As time passes, the object in question will move forwards along the sheet. However, if this object enters the depression caused by the weight (ie. the earth), it will begin to move to the left or right as well. It will still be moving forwards, but it's path will be affected by the curve of the sheet (ie. the curve of space/time). So, if we view this object it will appear to be curving (remember, left and right on the sheet are physical dimensions that we can see) when in fact it is the sheet itself that is curved.

      I know this is kind of confusing, but such is what happens when you begin to discuss relativity and gravity etc.

    7. Re:A Brief Explanation by 808140 · · Score: 4, Insightful

      Your question is a good one, but it has no answer. I'd like to explain why. It's a matter of philosophy.

      You see, science (especially in popular consciousness) is seen as the discipline which endeavors to answer the question "why?" with respect to various observable phenomena. These questions have been at the center of human thought for well, ever. We created religion in its various forms to answer this very class of questions.

      With the advent of science, it seemed as though we finally had a way to truly answer these questions, but unfortunately this stems from a fundamental misunderstanding of what science is. Science does not try to answer nor can it answer the why. The why has no answer.

      Let me explain. Science (and specifically the scientific method) is designed to determine, through experiment and falsifiability of hypothesis, the way the world behaves and to model its behaviour. Because these theories often have far reaching consequences, laymen (and even scientists, unfortunately) often make the mistake of thinking that their theories explain the why. But they do not; they simply explain the how.

      Let's explore this a bit. Newton's law of gravity did not explain why gravity exists. Why two bodies fall together is anyone's guess -- why, as a question, demands a reason. There may very well be a reason that two bodies fall together -- a popularly believed one is that some supernatural being designed it that way -- but physics does not, indeed, cannot, conjure up a reason by simply observing and modeling the way those two objects fall together.

      An example of this in more human terms: suppose you have a batty friend, and everytime you say foo, he says bar, like clockwork. You would quickly observe this and would, in your mind, be able to construct a hypothesis based on this behaviour -- when the subject hears foo, he says bar. And you could construct a series of experiments that test this hypothesis -- perhaps you would find that in the presence of blondes, he utters baz instead. This knowledge would allow you to predict his behaviour in certain situations, but it would say nothing whatsoever about his reasons for it. Nor could any amount of observation ever explain the reasons.

      Now, in physics this is obfuscated by the discipline's drive to isolate core phenomena. That is, it has been noted that often phenomena we observe are caused by smaller, less obvious phenomena. So, for example, attempts to make gravity fit into quantum mechanics have driven physicists to suggest that gravity as a force is mediated by a graviton, or what not. If this were ever demonstrated by experiment and became widely accepted, a laymen might ask, "why does gravity behave the way it does?" and a physicist might explain that it has to do with property xyz of gravitons. But this is not an explanation.

      This is simply telling the listener that the macroscopic observable phenomenon of gravity is actually made up of several, less easily observable phenomena. This is all well and good, but you'll notice that it actually explains "how" gravity works. "Why does my house keep out the rain?" "Because it has a roof." It seems logical, but it isn't. Because the roof is how it keeps out the rain -- the reason it keeps out the rain is something much more subtle, like, "Because the designers felt that the house's inhabitants would rather not get wet."

      Science answers the how of things, and it does this exceedingly well. It cannot (and for the most part, does not even attempt) to answer the why. But why and how are so muddled in the way people think that lots of folks (scientists included) are deluded into thinking that science will eventually explain the big questions like "why does the universe exist", and "why are we here."

      If you've ever asked a scientist the latter question, you may have gotten something along the lines of "We're here as a result of abiogenisis, followed by billions of years of evolution, catelysed by Darwinian na

    8. Re:A Brief Explanation by curtoid · · Score: 1

      Well think about a sheet stretched out very flat. On this sheeta are a number of very light objects. Now think of a lead weight placed in the center of the sheet. The sheet will bend into an inverted cone shape and all the items will slide towards the weight. Ta Da! Gravity!

      I have always had a problem with that illustration because the lead "weight" needs gravity to cause the depression, and the "light objects" need gravity to make them slide "downward" toward the depression.

      What gives?

    9. Re:A Brief Explanation by iso · · Score: 1

      I think you're thinking too much: it's only an analogy. There doesn't need to be a second force that makes the "indents" in the stretched sheet example. It's only stated that way to help people understand how gravity works on an example that's more easily visualized than warps in 3-dimentional space-time.

    10. Re:A Brief Explanation by IronicCheese · · Score: 1

      Actually, black holes are NOT "Very very heavy weights" as you suggest -- they are no more massive than the stars from which they are formed. What makes a black hole so strange isn't it's mass, but it's density - the amount of mass crammed into a very tiny volume.

      This matters: because all the matter is smashed into a small radius, it means you can get a lot *closer* to the all of mass of the object all at once.

      Step back from a black hole and it's going to tug at you no harder than a star of equal mass.

      As as astronomy professor of mine once said: Black Holes Are Only Weird Up Close.

    11. Re:A Brief Explanation by Council · · Score: 1

      I had the same question. The answer is that the four-dimensional space is curved, and the objects attempt to follow a four-dimensional straight line path, but since the space is curved, the path is curved.

      (There is an answer, or at least an answer on a satisfactory level. This question is not as meaningless as the other poster suggests.)

      --
      xkcd.com - a webcomic of mathematics, love, and language.
    12. Re:A Brief Explanation by Trogre · · Score: 1, Offtopic

      ... and how exactly are Adam and Eve or Noah's Ark falsifiable or contradictory in any way to modern science?

      --
      "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
    13. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Well that's easy. Adam and Eve or Noah's Ark are not falsifiable by science in the same way that Santa Clause and Pink Unicorns are not falsifiable by science.

    14. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Well, the theory is, our DNA has too many mutations for all organisms on land to have been reduced to small number of breeding partners in only the last couple thousand years.

    15. Re:A Brief Explanation by nothings · · Score: 1
      Nice post.

      I'd cut the agnosticism section (being agnostic towards any currently-unfalsifiable theory leaves you agonistic to a lot of silly things, like unicorns, or the theory that a human being travelling at 0.99c turns into a clone of Jesse Jackson; better to disbelieve and later change your mind), but whatever.

    16. Re:A Brief Explanation by 808140 · · Score: 4, Interesting

      Well, the Adam and Eve issue (as someone else pointed out) is that we don't have enough genetic diversity in one couple to produce all of humanity. Just consider the inbreeding problems that the royalty of Europe had a few hundred years ago due to intermarriage. If you wanted to populate the moon, for example, you could not just send one couple. Within a few generations, inbreeding related problems would be their downfall.

      Don't get me wrong, I think it's a nice story, and it can be used (like most mythologies) to explain social issues like morality and the like, but interpreted literally it falls rather short given what we know from observation about what happens when humans reproduce with their siblings and cousins for a few generations.

      Regarding Noah's Ark, this is actually a reference to a big issue in Darwin's time -- that of biological diversity. Again, Noah's Ark involves the idea of "a pair of every animal species" (which involves the same inbreeding issues as Adam and Eve) but even if you ignore that, there's the problem of the sheer number of species in the world.

      See, when the judaic tribes came up with this story, their world was much smaller, and the number of species much more limited. So it seemed reasonable that an ark of a particular size could hold all the animals in the world.

      But once naturalists started looking around, they realized that there were more species of animal than could possibly be held in just one ark. Furthermore, there's the issue of positioning. If you don't accept evolution, how did the animals get to their respective positions after the Flood? Did the kangaroo swim to Australia? All animals were created by god in static and unchanging way for some mystical purpose, according to religion, so after the Flood, all those animals needed to get to where the lived. Let's assume the Kangaroo did walk across Asia and then swim to Australia. Why aren't there any Kangaroos between Mt. Ararat and Australia?

      How do you explain phenomena like the Wallace Line between Bali and Lombok in Indonesia?

      The answer is, you don't. Noah's Ark may have been a localized occurence; there is evidence that suggests that the Mediterranean basin was once a wide and fertile valley and that a number of agricultural civilisations were destroyed as the water level rose. It's entirely possible, then, that some old guy built a boat and took his goats with him. But to extrapolate such a story to the entire world?

      I could see, if you believed in evolution -- and thought major speciation could happen in just a few thousand years -- that maybe back then there were just fewer animals, and that they subsequently evolved into their current form. Of course, this isn't consistant with scientific understanding of how evolution works.

      Or perhaps God created all those other Animals after the flood. Or maybe, there were many Noahs, in many different cultures, and they all built Arks. No matter how you try to explain it, though, the story as it stands is an explanation that doesn't scale.

      But that doesn't mean that it isn't a great story. I enjoyed it a lot as a kid. I'll tell it to my children. But it's a story. It's like the Church saying heliocentricity was bunk. They made a mistake. So what? If your belief in God depends on a literal interpretation of the bible or other religious dogma, it's a tenous faith indeed.

      Because, as I pointed out, Science can only replace the mythologies produced by religion, but it will never be able to replace the core reason for the existance of religion -- to explain why things are the way they are. There's no reason to feel threatened about modern evidence falsifying or rendering unlikely stories written by nomadic tribes millenia ago.

    17. Re:A Brief Explanation by 808140 · · Score: 4, Insightful

      I don't know... there's nothing silly, on the face of it, about unicorns. Why shouldn't there have been a horse with one horn at some point in time? It, like many other things, might just be extinct. Anyway, stranger creatures have walked this earth.

      As for the Jessie Jackson bit, that truly is silly. But I think it's a different issue than the existance or non-existance of God, because your scenario serves no purpose. Don't you ever wonder why the universe exists? It all seems so perfect. I see the existance of benevolent white bearded super-being as the willfull creator of the universe as a bit of a stretch, granted. But I guess if someone were able to offer evidence that the universe had been somehow engineered, I wouldn't really be surprised. But I would just replace my "why does the universe exist" question with "why does God exist", which is equivalent. It's the whole "Unmoved mover" thing. My human belief in causality makes me wonder why things are, and anything which exists for no reason confuses me.

      To me, "the universe exists for no reason" and "God created the universe for a reason, but God exists for no reason" are equivalently frustrating belief systems.

      But I'll stay open-minded. I just wanted to underscore that I'm not against the notion of God in principle. I just don't think it's supportable.

    18. Re:A Brief Explanation by Anonymous Coward · · Score: 1, Interesting

      All this is good, but I do have a slight philosophical objection to the rubber sheet explanation of gravity. It seems to me to be a kind of circular argument: It requires a gravity field to make the objects on the sheet model a gravity field. OK so there is no gravity field, there is just a distortion of space, which in the presence of a "metagravity" field means that the objects follow the curved path they would follow if there actually was a gravity field. The metagravity field then requires another distorted space to explain it, with a metametagravity field to go with it, and so now it is rubber sheets all the way down. (instead of turtles...)
      OK, I think in fact that the rubber sheet business falls into the general category of "lies to Children", and that if I understood the maths it would be clearer. My take on it is that the physicists and theorists are trying to accomodate the problem of action at a distance as exemplified by gravitational, magnetic, and electric fields. We tend in our human way to treat these things as if there was a kind of invisible string pulling between the two objects, although we know this does not make sense and we are not happy about the idea of massless invisible strings anyway. (No connection with string theory which is a whole other bag of worms...I think!) So how does one object "know" that the other object is there anyway? And then there is the point that if the objects are moving, either the information about the presence of the other must travel instantaneously or it must travel at some restricted speed...Einstein tells us, and observations AFAIK confirm, that in fact the one object is responding to where the other object was in the past, with the limit on the rate of the information being c.

      So I think in fact there is room for someone with a really good grasp of the whole thing to come up with a better way to explain this to the ignorant (I include myself) than the rubber sheet model.

    19. Re:A Brief Explanation by Capt'n+Hector · · Score: 1

      It's not a stupid question. Indeed, I find the bowling ball visualization helpful, but in the end lacking. Not because it relies on the very force it attempts to show, but because it's far more complicated than need be. It relies on tension, gravity, friction, etc. SIMPLIFY! Gravity is a field force, that's all. There's one gravitational field, and each mass unit affects divergence at its location. This drag phenomenon might be as simple as the curl operator. Can somebody PLEASE explain this drag phenomenon without waving their hands?

      --
      Quid festinatio swallonis est aetherfuga inonusti?
      Africus aut Europaeus?
    20. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Now I agree with your assesment of science only able to apply to the "how" questions, I don't agree that there is currently enough scientific evidence to falsify what you call "ridiculous mythologies".
      Scientists researching in the fields of geology, evolution, fossil record etc need to distinguish far more clearly between observed facts and hypothosis that are based on their own assumptions.
      Fact, there are fossils in the ground. Fact, there are lots of different layers of sediment. Fact, there are slightly different amounts of C14 in some rocks / fossils. We also have observed how DNA is recombined from both parents, and yes there are occasional copying errors / random mutations.
      Everything else contained in the various theories on origins are based on the assumptions of the observer.
      Radio carbon dating makes a huge number of assumptions and has been proven to give unreliable results.
      Here's some more facts for you that most scientists ignore. There seem to be NO missing links in the fossil record. None, Nada, Zip, Zero. I'm so confident of this that I challenge you to prove me wrong. The further down through the layers you look the more identical fossils you find, and are identical to living specimens.
      I'm not saying there is no variation, it's obvious from looking at dogs, cats, horses, finches, moths, etc that variations in a species are easy to obtain through selective breeding. But this variation has limits.
      Where are the animals in the fossil record that have half of a working lung? half of the protiens involved in the blood clotting process? half of a circulatory system? half of the photo sensive cell in the retina?
      We don't even understand gravity properly yet at large scales (MOND / pioneer anomoly / etc), how can we possibly project backwards to the begining to know what the early universe was like?
      Anyway that's enough of a rant from me... As you said scientists should realise they can't answer the why questions and keep to the how's. And since we can't go back in time and observe what really happened, the how's and why's of origins should be left alone.

    21. Re:A Brief Explanation by Goosey · · Score: 1

      Very well written. This puts into words a lot of thoughts I have been having for quite some time.

      More then anything I love your statement: " If your belief in God depends on a literal interpretation of the bible or other religious dogma, it's a tenous faith indeed."

      You really hit the nail on the head my friend.

      --
      --- "End Of Line" - MCP
    22. Re:A Brief Explanation by complete+loony · · Score: 0, Offtopic

      We've been inbreeding for a long time, and we've lost (or spread very thin) most of the information that a hyperthetical adam or noah would have had in his DNA. Natural Selection only guarantees that the information in use will remain viable. If a section of DNA is not required there is no selection pressure to ensure it remains accurate, and the information may be lost. Inbreeding is bad because it reinforces the errors that are already there, and reduces redundancy, it doesn't automatically create problems. According to the bible, noah was born less than 1000 years after adam, and after about 10 generations (from memory). Not nearly enough time to develop heaps of nasty copying errors. Also there wasn't only one couple on the ark, there was noah, his wife, their 3 sons and their wives (and maybe some daughters, or younger children, they tend to get ignored / edited out). That's at least 5 genetically different people which should be fairly viable.

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
    23. Re:A Brief Explanation by complete+loony · · Score: 1

      "Why shouldn't there have been a horse with one horn at some point in time"
      Or a bad chinese whispers description of a rhinoceros.

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
    24. Re:A Brief Explanation by Anthony+Boyd · · Score: 1
      our DNA has too many mutations for all organisms on land to have been reduced to small number of breeding partners in only the last couple thousand years.

      But I don't know of any religion that says we sprouted up in the last 2000 years. I know many who mention a messiah 2000 years ago, but by that point, humanity had been humming along for quite some time.

      Perhaps you're thinking of Biblical lists of ancestry. For example, in the Bible it traces back some leader's ancestors all the way to Adam & Eve, so you can calculate the age of humanity by allotting a certain amount of years per generation. That's the "young Earth" school of thought, but it suggests only that humans have been around for about 10,000 years. It's called "young Earth" because most of those people believe Earth & Humans are on roughly the same timetable. Although I'm religious, I don't believe that. I believe the lines of ancestry are made up to impress readers at the time, and that Earth & Humans didn't spring into existence at the same moment, anyway.

      I have heard interesting things about our genes. For one, the Discovery channel ran a feature on a near-extinction event that appears to have reduced the human gene pool down to just a few hundred or thousand people, about 70,000 years ago. Could have been something struck Earth, wiped out a lot of life except for a few people in boats. It's a possible real-world source of the Noah's Ark story, although I personally suspect whatever humans experienced 70,000 years ago, they survived because they were deep, deep cave dwellers. And I've also heard of what some scientists call Adam & Eve -- a common ancestor that apparently can be seen in everyone's genetic makeup, regardless of race. But I never looked into that very hard. The few times I heard of it, it always sounded like it hadn't solidified.

    25. Re:A Brief Explanation by dasunt · · Score: 3, Informative

      Well, the Adam and Eve issue (as someone else pointed out) is that we don't have enough genetic diversity in one couple to produce all of humanity. Just consider the inbreeding problems that the royalty of Europe had a few hundred years ago due to intermarriage. If you wanted to populate the moon, for example, you could not just send one couple. Within a few generations, inbreeding related problems would be their downfall.

      Bad example -- the Eve Hypothesis seems to indicate that all of humanity is decended from a relatively "small" population of humans (where "small" is defined as less then 20k).

      There is also a corresponding Adam Hypothesis

      In science, tiny populations can give rise to large populations (Founder's Effect), although sometimes there are side-effects.

      Wisent (European Bison) are all decended from twelve individuals. Wisent bulls suffer from some lack of diversity, only having two distinct Y-chromosomes in their genetic pool, but there are only limited effects from interbreeding.

      Golden Hamsters tend to be all decended from one litter found in Syria in 1930.

      IIRC, Noah was supposed to have several people on the Ark -- himself, his children, and his children's spouses. Although clearly not an optimal setup, it would probably be enough to prevent the species from dying out.

      I wouldn't be surprised if some islands in the world started out with roughly the same population.

      Don't get the wrong impression -- I'm not arguing for Creationism or literal interpretations of the bible. I just don't want to see bad science being repeated.

    26. Re:A Brief Explanation by mollymoo · · Score: 1
      All this is good, but I do have a slight philosophical objection to the rubber sheet explanation of gravity. It seems to me to be a kind of circular argument: It requires a gravity field to make the objects on the sheet model a gravity field.

      It's not an explanation of gravity, nor is it the definition of general relativity. It's a way of looking at a simplified mathematical model of general relativity so we can get some intuitive idea of what it's all about. Our heads just don't work with warped 4-dimensional space-time, they haven't evolved to as the effect is not directly observable on Earth-being scales. It is literally beyond our imagination. What the sheet model does is enable us to visualise things like how something can travel in a straight line yet apparently go round a corner at the same time.

      Don't take it too literally, think of it more as a graph than a diagram. Don't expect to be able to "see" it in all its multi-dimensional glory in your mind's eye. I tried for a years during and after my physics degree and eventaully gave up and stuck with mental images in fewer dimensions and a whole bunch of maths.

      --
      Chernobyl 'not a wildlife haven' - BBC News
    27. Re:A Brief Explanation by akac · · Score: 1

      This is hooey. Even National Geographic's recent articles on the Phoenicians states what most scientists in this field know - ALL living man comes from one single man. They can trace all Arabs (as the example used in this story) to a single man living 30,000 (their timeline) years ago.

      Here is their online snippet:
      http://magma.nationalgeographic.com/ngm/ 0410/featu re2/index.html

    28. Re:A Brief Explanation by 808140 · · Score: 1

      Everything you have said is true. Unfortunately, it isn't all that applicable. For one thing, the Eve and Adam hypotheses, while named for Adam and Eve, do not postulate the existance of one individual or couple that seeded all of humanity -- they simply suggest that at one point, there weren't many humans. A population of 20 thousand is quite different from one couple. The fact that we are able to note, from mitochondrial DNA, that these sorts of "population bottlenecks" occured in our past doesn't really have any bearing on the plausibility of an Adam and Eve scenario.

      Now, your animal examples are interesting but irrelevant, also. How do we know that Wisent Bison are descended from 12 individuals, or that Golden Hamsters are descended from just one litter? Subsequent lack of genetic diversity. Just as we know that the population of Iceland is descended from just a few Norse families that settled there long ago, our DNA provides evidence of genetic diversity or lack thereof. On a whole, we humans are rather diverse, genetically. Not so diverse that we can't interbreed, but diverse enough that our initial "seed" population could not have been just one couple.

      So yeah, I think I stand by what I said in my OP. I don't think I'd call it bad science. Your examples are interesting but don't matter because a) they either talk about animals other than humans, or b) suggest that humans could have evolved from a population of around 20k individuals -- rather more than a couple, which is the idea I'm trying to refute, at least in its literal interpretation.

    29. Re:A Brief Explanation by 808140 · · Score: 2, Interesting
      That's at least 5 genetically different people which should be fairly viable.

      Unfortunately, it's not. How many people are needed to create a genetically viable population varies very much on the individuals concerned, but the lowest number I've ever heard is 60 -- 60 completely unrelated individuals.

      Rather more than 5, at least.

    30. Re:A Brief Explanation by Logi · · Score: 1

      They may be able to find a single common ancestor to all currently living Arabs, but there will have been genetic material injected from other sources. His 12 sons' 48 wives, or what have you, for starters.

      So while this is an interesting factum, it isn't really relevant to this particular point.

      --
      Logi - I can do anything, but not everything.
    31. Re:A Brief Explanation by Logi · · Score: 1
      We've been inbreeding for a long time, and we've lost (or spread very thin) most of the information that a hyperthetical adam or noah would have had in his DNA.

      But that's the exact point right there, if there were only 5 people who re-populated the earth, there wouldn't be any other genetic information to spread Adam's or Noah's genetic information over, there wouldn't be very much to mix it with. p Taking any given bit of genetic material from any random person could only have one of the 5 values (with possible crossovers), discounting mutation. For mutation to account for the diversity observed in the human population in the few thousand years since Noah, we would need much higher observed mutation rates and, probably, too high for the species to survive.

      --
      Logi - I can do anything, but not everything.
    32. Re:A Brief Explanation by ives · · Score: 1

      gravity is not really a pull from one object to the other. What it is is a distortion in the fabric of space-time. What does this mean? Well think about a sheet stretched out very flat. On this sheeta are a number of very light objects. Now think of a lead weight placed in the center of the sheet. The sheet will bend into an inverted cone shape and all the items will slide towards the weight. Ta Da! Gravity!


      Call me stupid, but I don't get this explanation. In your model, the only reason these items slide towards the weight is because earth's gravity pulls them down into the inverted cone. So without earth pulling these items nearer, there would be no movement at all.
    33. Re:A Brief Explanation by nusuth · · Score: 1

      There is common mother to us all and there is a common father to us all but the two have never met. The genetic Adam is younger than half the age of genetic Eve. And both are a lot younger than first humans around.

      --

      Gentlemen, you can't fight in here, this is the War Room!

    34. Re:A Brief Explanation by dasunt · · Score: 1

      From your original post:

      Within a few generations, inbreeding related problems would be their downfall.

      From your most recent post:

      So yeah, I think I stand by what I said in my OP. I don't think I'd call it bad science. Your examples are interesting but don't matter because a) they either talk about animals other than humans, or b) suggest that humans could have evolved from a population of around 20k individuals -- rather more than a couple, which is the idea I'm trying to refute, at least in its literal interpretation.

      Basically, I agree with you -- there is no compelling evidence to a literal interpretation of Noah's Ark.

      OTOH, inbreeding would not have been their "downfall", to use your words. Sure, humans aren't golden hamsters or wisent bison. But I cannot think of any difference between us and these animals which would cause a tiny population of humans to die out due to inbreeding. Noah's ark, according to the bible, had 8 people on board, including 3 breeding pairs of adults. That is more genetic diversity then hamsters.

      (Btw, we know that the wisent are decended from 12 individuals and that most golden hamsters are decended from one because of historical records. Its the lack of genetic diversity that indicates human population bottlenecks, for example.)

      Now, if you were arguing that there is too much genetic diversity in humans for a literal interpretation of Noah's ark, you'd have a valid point.

      But if you argued that a small group of people couldn't survive due to genetic diversity, any learned individual will disagree because your point is invalid.

    35. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Literal interpretation of the bible is futile at best.

      Adressing the issue of Adam and Eve, I would like to make a few observations, without taking a stance:

      * Recent experiments show that the Y-chromosome of a large number of tested males from two different, geographically seperated peoples was very likely to be descended from a single Y-chromosome, which makes it conceivable that a single male originated at least a significant portion of the human population.

      * Inbreeding tends to perfect the species as a whole, because defects become crippling so much more quickly, leading to the defects dying out faster than under normal circumstances.

      * Assuming a "perfect" point of origin- hereunder defined as a being without any genetic traits that would cause defects when propagated, whether recessive or not- there would be no inherent problem in inbreeding.

      * The Jews mention Lilith, who was created equal to Adam, and Eve, who was created an inferior being. This gives us an, admittedly, small but highly varied gene pool to start from.

      * Cain and Abel, descendent from Adam and Eve, went out and found women to be with, the Daughters of Kanaan IIRC, which clearly shows that there were other people in the world, according to the biblical world view, even if interpreted literally. Presumably the story of the Garden of Eden refers to one place.

      * If you consult the Biblia Sacra Vulgata, you will find that there is an interesting use of singular/plural form, to the effect of saying something like "And I shall create mankind in our image". This indicates that we are not talking about using first person plural as a way of indicating elevation (as with the plural "you" vs the singular "thou" in English), but rather a use of plural that indicates the presence of other entities to which the deity described in the bible makes reference.

      * As to the fabled 6 days to create and 1 day to rest, the bible states elsewhere that in heaven one day is as a thousand years, and a thousand years is as one day, which can easily be interpreted to mean that time simply has no meaning there, perhaps even that it is a place outside the normal "space" of causality, hence "solving" the chicken-and-egg problem of a creator creating everything.

      * Obviously, rather than reading the bible literaly, one should try to read the underlying meaning. We must bear in mind that we are not talking about one coherent work, unchanged throughout the ages, written by someone of our time. There will be cultural differences, assumptions about common knowledge, problems with words that have changed meaning over time, translation errors, problems with punctuation and interpretation, and so forth. As an example, Hebrew was originally spelled without the markings that indicate vowels, causing some words to have the same spelling. A classic example is in the passage "Thou shalt not suffer a witch to live", where the word for witch can also, depending on the vowels, be interpreted as "female poison-assassin". The meaning becomes radically different, and could be transposed to our own time and culture as "You should not let someone live that as their profession kills humans on assignment from other citizens".

      As I said, I am not trying to say that I necessarily agree with what the bible says. I am perhaps saying "some assembly required".

    36. Re:A Brief Explanation by rembem · · Score: 1

      The word 'why' means different things in different contexts. A why-question can either ask for cause or morality. Scientist tend to answer the cause question, while religious types tend to concentrate on morality. The same seems heuristically true for males vs females.

    37. Re:A Brief Explanation by sploxx · · Score: 1

      Hey, I was looking down the thread and thought about writing a similar post.

      But I could have never done that with my poor english as well as you did. Your post is reall great!

      Studying physics myself, I have now bookmarked it in my folder of slashdot gems :)

    38. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      So that explains Kentucky, but what about Mississippi?

    39. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      That's crazy talk. That single common ancester is alive today, and has slept with billions of women over the years.

      Wilt Chamberlain's got nothing on that cat.

    40. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      It's a better explanation that you indicate. Forget about tension, gravity, and friction, if you like and just accept that a massive object distorts spacetime around it. (Why? Like the previous poster said, we don't know why.) So you have this distorted membrane. Now try to make an object move in as straight a line as possible on this membrane. (Define "as straight a line as possible" as the shortest distance between two points.) Well, it can't be truly straight since the membrane is distorted. So... in GR objects still move in straight lines, they just do so in a curved spacetime, hence their paths are curved.

      Another objection some people have is that to imagine a 2D membrane that is curved, you have to embed it in 3D (actually, for some kinds of curvature you need 4D). But from a mathematical standpoint that is not necessary. You can describe the intrinsic curvature without reference to additional dimensions; however it can be proved that for any given intrinsic curvature you can find a membrane embedded in a higher dimensional space that has that curvature. So... is our 4D universe embedded in a higher dimensional universe (and I'm not talking about string theory here)? Well, who knows. It is not something addressed by the theory.

      As for gravity being a field... yes, to a first approximation (i.e. not around black holes and such things), it is indeed a field. (I say "to a first approximation" because a field lives in some sort of defined spacetime, whereas the gravitational field actually defines the shape of spacetime, so it gets complicated when gravity is strong.) But it's a tensor field, and I've yet to find anyone who thinks that tensors are more intuitive to think about than membranes.

      However, if it helps, frame-dragging is analogous to the generation of a magnetic field by a current loop (a rotating object generates a mass current) and you can think of the extra force on an orbiting object as due to the force of this "gravitomagnetic field" on the moving object.

    41. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      As usual lack of data leads to confusion, as someone else on a slighjtly different thread already pointed out, as long as you lack errors, inbreeding isn't a problem. Though you would definitly not get much diversity any time soon from that. Now in the case of the wison bison, it's known they had prolonged periods of small population, this leads to the hypothesis that all those bottlenecks may well have caused a heavy selection against errors, and thus a fairly error free line, allowing them to survive the 12 individuals bottleneck.

      I don't know anything about the hamsters, but then the links are really scarce on data themselves, and in fact state there are numerous important unknowns. So while interesting, someone aught to more properly research it.

      Quickshot

    42. Re:A Brief Explanation by jsebrech · · Score: 1

      There is a premise to your post you didn't mention. You assume there is a why to accompany the how. I see no reason to assume that. It might just be that things are the way they are, without a reason. In that case "why are we here?" gets the answer "because if we weren't we couldn't ask ourselves why we are here".

    43. Re:A Brief Explanation by srleffler · · Score: 1
      Don't put too much importance on the whole "rubber sheet" thing. It's just a model, designed to give non-physicists a sense of how general relativity works. It's not an accurate description of things.

      You are quite right that the model assumes you have gravity to pull things towards the depressions in the rubber sheet. The point of the model is to express how, in GR, gravity does not directly act from one object on another, but rather the gravitational field of an object distorts the space around it in such a way as to cause other objects to be pulled toward it.

    44. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      So I think in fact there is room for someone with a really good grasp of the whole thing to come up with a better way to explain this to the ignorant (I include myself) than the rubber sheet model.

      It's the same 'force' that moves you through time.

      Head spinning yet? :)

    45. Re:A Brief Explanation by curtoid · · Score: 1

      So, what you're saying is that you use your innate understanding of gravity to visualize how this analogy attempts to demonstrate how gravity works....

      You can't use the word "definition" in the definition of "definition."

    46. Re:A Brief Explanation by wjwlsn · · Score: 1

      This has got to be one of the best Slashdot posts I've ever read. Bravo. I wish I had mod points to give you, and that moderation wasn't cut off at +5.

      --
      Getting tired of Slashdot... moving to Usenet comp.misc for a while.
    47. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      I don't agree that there is currently enough scientific evidence to falsify what you call "ridiculous mythologies".


      If the "ridiculous mythologies" include a Earth younger than billions of years, or life that doesn't share a common ancient ancestor, then yes, there's more than enough evidence to falsify them, and has been for at least a century.


      Radio carbon dating makes a huge number of assumptions and has been proven to give unreliable results.


      Radiocarbon dating has been calibrated against other, independent dating methods, and has been shown to be quite reliable -- and the extent of its unreliability is quantified. There are some circumstances where it doesn't work at all, and we know what they are, and don't apply that dating method to those circumstances.


      There seem to be NO missing links in the fossil record. None, Nada, Zip, Zero. I'm so confident of this that I challenge you to prove me wrong.


      Of course it's impossible to prove you wrong, because your definition of "missing link" won't allow it. Of course, that has nothing to do with the evidence that all life on Earth evolved from a common ancestor.


      But this variation has limits.


      Why? And what are those limits? Are they enough to disprove evolution? How do you know?


      Where are the animals in the fossil record that have half of a working lung? half of the protiens involved in the blood clotting process? half of a circulatory system? half of the photo sensive cell in the retina?


      Don't be an idiot. This is the usual strawman characterization of evolution, which has nothing to do with the real thing. Evolution does not work by producing "half an lung", then filling in with a "whole lung". Or for that matter, "half a photosensitive retina cell". A retina cell wasn't built by putting together two halves of a cell. It came from an ordinary, non-retina cell, with a mutation to produce a photosensitive chemical. A lung wasn't build by gluing together two half-lungs. Lungs came from gradual changes to pre-existing structures (ultimately, gills); gills came from still simpler organs, etc. We can see a whole range of oxygen-exchanging organs in existing life even today, from very primitive to very complex. Likewise, blood clotting started out as a simpler process... I don't know the mechanisms, but it could have been just one protein that clotted a little bit, or it could have been a bunch of proteins that all did different independent things, and mutations caused intermediate proteins that catalyzed them to start working together. Evolution does not proceed by starting out with a useless "half of something".


      We don't even understand gravity properly yet at large scales (MOND / pioneer anomoly / etc), how can we possibly project backwards to the begining to know what the early universe was like?


      We do understand gravity pretty well at large scales. MOND (which is probably wrong anyway) and the Pioneer anomaly cannot change the history of the universe from an early Big Bang. At best, they can change some details of how matter clumped together later.


      As you said scientists should realise they can't answer the why questions and keep to the how's.


      Expansion of the universe from a hot and dense state, and evolution of life, are how's, not why's.


      And since we can't go back in time and observe what really happened, the how's and why's of origins should be left alone.


      Don't be ridiculous. That's like saying that historians should quit because they can't go back in time, or forensic scientists shouldn't bother trying to solve crimes, because they can't go back in time to witness them. We can reliably infer an enormous amount of information about the past by studying the present, and only someone profoundly ignorant of science would think otherwise.
    48. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      My God, what a fantastic comment. Thank you so much for helping me understand that. I always felt that Science vs. Religion was a false competition. Excellent, excellent, excellent.

    49. Re:A Brief Explanation by Dulimano · · Score: 1

      I really liked your explanation about scientists answering why-questions with how-answers. But let me mention a possible point where science gives a why-answer in this sense. The Anthropic Principle is generally frowned upon, because the answer it gives is unsatisfying and can even be considered nihilistic. But it is a why-answer.

    50. Re:A Brief Explanation by stonecypher · · Score: 1

      Why shouldn't there have been a horse with one horn at some point in time?

      Given their purportedly massive stature and resistance to being cut, there are many which suggest that the unicorn legend is the descendant of early reports of rhinoceri.

      --
      StoneCypher is Full of BS
    51. Re:A Brief Explanation by complete+loony · · Score: 1
      The variation we see doesn't rely on mutation, It's a product of the way we reproduce. All the information we now see spread out and specialised in the DNA of various people groups (who have had some long periods of isolation and inbreeding) could easily have been contained in 1 person (or 5...). It's impossible to say just what the DNA of a hypothetical adam or noah would have contained.

      There are many parts of DNA that deliberately recombine in different ways (take a close look at antibodies if you don't believe me). All of the information for different hair colours, amounts of skin pigment doesn't require much change in DNA at all. While the important stuff in DNA that controls how our bodies work has remained nearly completely unchanged across all people groups (besides the occasional genetic defects).

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
    52. Re:A Brief Explanation by GooberToo · · Score: 1

      This is the best read I've had on /. in a long while. Good job!

    53. Re:A Brief Explanation by GooberToo · · Score: 1

      Please allow me to play devil's advocate here.

      Well, the Adam and Eve issue (as someone else pointed out) is that we don't have enough genetic diversity in one couple to produce all of humanity. Just consider the inbreeding problems that the royalty of Europe had a few hundred years ago due to intermarriage. If you wanted to populate the moon, for example, you could not just send one couple. Within a few generations, inbreeding related problems would be their downfall.

      Or, given enough time, over enough generations, might explain the genetic diversity. IIRC, if you can survive past 8-10 generations, and manage the breeding, you're not doomed. In the long run, over many thousands of years, diversity can be restored. If you stop and think about it, people still need to get blood tests to guard against genetic problems. That, to me, suggests that we not as diverse as is commonly believed.

      Regarding Noah's Ark, this is actually a reference to a big issue in Darwin's time -- that of biological diversity. Again, Noah's Ark involves the idea of "a pair of every animal species" (which involves the same inbreeding issues as Adam and Eve) but even if you ignore that, there's the problem of the sheer number of species in the world.

      Actually, last I heard, the story of Noah's Ark was pretty well supported. The problem is, most everyone has the wrong story. Last I heard, the major problems that traditionally exist for Noa and his boat, actually spring forth from bad translations, plain and simple. Accordingly, it seems that the hebrew word for world and land (meaning, the region), are the same word. Which means, people decided that since it was a biblical story, it surely must mean the larger of the two. The geo record does support vast floods of epic proportions, specific to the region, which does match up with the timeline. Once we accept that, since he wasn't carrying ALL of the world's animals, only regional animals, fitting them all on the boat becomes feasible. Then, since the regional animals are free to breed to non-regional populations, the generic diversity is free to remain just that, diverse.

      Long story short, Noa's Ark is really a story of theologically driven, bad translations. Who knows if Noa really had his boat, but the evidence, when properly viewed, does suggest that it's well within plausibility. And, it's supported by the readily available evidence.

    54. Re:A Brief Explanation by GooberToo · · Score: 1

      Basically, I agree with you -- there is no compelling evidence to a literal interpretation of Noah's Ark.

      Actually, there is, assuming you hear the original story. Granted, "compelling", might be a bit strong. Nonetheless, there certainly is a fair amount of supporting evidence. Once you start at square one, with the original hebrew (IIRC) text, you'll see that it was NOT a global flood. Rather, it's a story of an epic, regional flood. The geo record and timelines do match up.

      Periodically, there is a show on Discovery Channel (IIRC), which does a pretty good job of scientifically supporting the story. For them, after scientifically ruling out the original, commonly repeated, story, they went back to the actual text. There, they found, that an obvious translation error had occured and had been perpetuated through the years. The revised story, as originally penned, does seem to have some amount of "leg" to stand on.

    55. Re:A Brief Explanation by one-of-many · · Score: 1

      Is that a scientific principle? It's wiki page made it sound more philosophical. Most Christians believe in an interventionist God (one who interacts with our universe, created it). Science should try to decern the methods in the causal chain (the How). It should search for the first cause because we will learn alot along the way and we are curious. But since we can not observe a universe being born and not being born. Science will not be able to make a good guess about the first cause. http://en.wikipedia.org/wiki/Anthropic_principle

    56. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Brilliant troll.

      Simply brilliant.

      You ought to submit that to Trollback.

      Seriously, one of the best trolls evaaah!!

      Hats off, mate.

    57. Re:A Brief Explanation by Anonymous Coward · · Score: 0

      Dude! Where do you come up with this stuff? :-)

      Brilliant troll, mate.

      You ought to submit this to Trollback, too.

      Seriously, awesomely well done mate!

      Hats off. You're my new troll God.

  23. No by Rufus88 · · Score: 4, Informative

    No. Scientific theories don't get promoted to laws. Laws are observations of things that appear to hold true. For example, the law of gravity ("what goes up, must come down"), Snell's Law, Ohm's Law, the Law of conservation of Mass/Energy, the Laws of Thermodynamics, etc. A theory is an *explanation* that models some observed phenomena and which has the power to predict other phenomena. Theories are either falsified (i.e. proven wrong), or are confirmed (i.e. shown to be consistent with some new observation.) Theories are never proven true; rather, they are simply confirmed to a greater and greater degree. No matter how well a theory is confirmed, it can always be falsified by a new experiment testing some as-yet-untested prediction. In this case, the theory is either revised to account for the new observation, or it is simply discarded.

    1. Re:No by Jason+R · · Score: 1

      Not to be stupid, but why doesn't Ohm's law fail at small observation limits? I mean, it's predicated on taking a macroscopic view of current flow. Consider looking at individual electrons, and it becomes a statistical average and can't predict the flow rate at really small quantities. Not meaning to be pendantic, but I don't see how a macroscopic prediction can be a law when we can't predict individual element movement. Might sound dumb, but there has to be concrete difference between a law and a theory.

    2. Re:No by Anonymous Coward · · Score: 0

      Well, that's fine. Ohm's law is accurate within a certain domain. So is Newton's law of gravity. I mean, take those Australians. They call it the "down under", correct? Well, their maps indicate that they are infact on top, and their toilets flush the opposite way (how disgusting is that), and objects fall towards the sun, etc.

      So, I conclude that the law of gravity only applies to the Northern Hemisphere, and that laws are only valid in certain circumstances.

    3. Re:No by Anonymous Coward · · Score: 0

      As an Australian, I theorise that gravity applies only in the Northern Hemisphere due to its inhabitants being so dense...

    4. Re:No by Anonymous Coward · · Score: 0

      By the way, this has a funny consequence. If you find a single theory T which predicts everything you needed two theories A and B before, this is meant to be a "good theory": it simplifies things. Problem comes when you find two theories T and U which combine the same two theories A and B - you can't tell which one is better as long as you can't test a prediction for which they differ!

      So as a rule of thumb: a theory that can't be proven wrong is worthless, and is often called philosophical. But that still doesn't mean it won't attract thousands of theoreticians (see also: string theory) :-]

    5. Re:No by Rufus88 · · Score: 1

      Are you saying that string theory does not make falsifiable predictions?

  24. Whats frame dragging? by EvilGrin666 · · Score: 4, Informative

    For those of you like me who didn't have a clue what this article is about check out the Wikipedia entry for frame dragging.

  25. /whips out Hempel by Anonymous Coward · · Score: 0

    >Yes, this makes truly proving anything in the physical world basically impossible.

    Indeed, an infitite number of theories will explain observable phenomena; no theory can be "proven" based on your criteria. Under a verificationist criterion of meaning, unfalsified is as good as you can get.

    It bothers me more when people say evolution is "not a law but just a theory" as if they know what on God's green earth they're talking about.

  26. Space and time are necessary to define each other by Anonymous Coward · · Score: 0

    Then can we infer time dilation at the locations on the map (see CNN article) that report high gravity distortion?

    Progman3K

  27. Mayube something simpler? by Midnight+Thunder · · Score: 1

    Although this probably a good explanation, couldn't something simpler be at play, such as:

    - atmosphere: although it is very thin by that point there is probably still enough to cause drag, even if we are talking decimals
    - Earth gravity: the Earth still has a gravitational effect even at that distance, so taking into account the pull down would reduce the forward vector of the satellites
    - Moon or Sol gravity: pretty much anything large enough has a gravity that will effect objects close by.

    Because we can't rule out other simpler causes, such as grativational or atmospheric drag, I am not ready to say this confirms relativity, in the physical sense. Then again I must admit I do view relativity as more as an observational theory than a physical theory.

    --
    Jumpstart the tartan drive.
    1. Re:Mayube something simpler? by Anonymous Coward · · Score: 0

      All of the effects you list are predictable or measurable. The researchers who did this are a probably a lot smarter than you or me; I'm sure they've eliminated other variables. To suggest they simply overlooked the possibility of other effects is silly; discerning signal from noise the first (perhaps the only) thing experimentalists think about, and they're damn good at it.

    2. Re:Mayube something simpler? by John+Meacham · · Score: 3, Informative

      Frame dragging IS the simpler explanation :)

      frame dragging was predicted in the early 1900s by the various equations that make up relativity. if we were to observe that it wasn't happening and some other effect were causing it, then that would be very odd indeed, as that would imply that all the equations which have been right in so many other ways are wrong in this one little regard making things much much more complicated.

      The simplest possible explanation for this is frame dragging.

      Also, the gravity effects you mention would not affect the sattelite in this way, a downward pull has no effect on the horizontal motion of a satellite and the moon and suns gravity can easily be accounted for. Also, imagine the root cause was the moon and suns gravity, then that would imply there is something fundamentally new about the gravitational laws we do not yet understand, which again is very interesting and much more complicated than frame dragging.

      --
      http://notanumber.net/
    3. Re:Mayube something simpler? by Fortran+IV · · Score: 3, Interesting

      You're not recognizing just how sensitive and sophisticated measurements and calculations of Earth's gravitational field have become. It's been well over a decade now since I read of how a satellite was used to create new and detailed maps of the ocean floor by measuring local variations in sea level; because rock is more dense than water, a seamount a mile below the ocean's surface creates a slight increase in the local gravitational pull, causing the ocean to hump up slightly above the mount.

      The article doesn't say, but I would hope that the satellites were launched to orbit with Earth's rotation, so that frame dragging would accelerate them in their orbit, which would rule out atmospheric drag. I'd guess, though, that after 40+ years of satellite tracking such drag can probably be predicted to several significant digits, as can the gravitational effects of the Moon and Sun.

      And, BTW, general relativity is a very physical theory. Last I heard, it's still the best explanation of why Mercury wobbles back and forth instead of being firmly tide-locked.
      --
      I figure by 2030 or so my 6-digit UID will be something to brag about.
    4. Re:Mayube something simpler? by Anonymous Coward · · Score: 0

      OMG, We never thought of that! Sorry for wasting everybody's time.

      - Ignazio Ciufolini & Erricos Pavlis

    5. Re:Mayube something simpler? by nerdguy569 · · Score: 2, Insightful
      atmosphere: although it is very thin by that point there is probably still enough to cause drag, even if we are talking decimals
      - Earth gravity: the Earth still has a gravitational effect even at that distance, so taking into account the pull down would reduce the forward vector of the satellites
      - Moon or Sol gravity: pretty much anything large enough has a gravity that will effect objects close by.
      I do believe that they factored in the earth's gravitational pull, considering that is what kept it in orbit, and what causes frame dragging.
      additionally, the moon and Sol's gravity would most likely be the second two things to be factored in, and cause perturbations far greater than 6 feet.

      and the atmosphere and a few other more minor effects are what the Gravity Probe B people are critical of. However, it seems that the orbit of LAGEOS II is at 5,782 kilometers, according to NASA Spacelink at that altitude, the amount of atmospheric drag is greatly overcome by many other effects such as the radiation of the sun, which pushes the satelite slightly, the same way some people have speculated for years that we could use that same solar radiation to travel to other planets, using a solar sail.
      My guess is that they would have checked most of the sources of error which you listed before going to press.
      --
      In the future, we will all be very smart or very stupid.
    6. Re:Mayube something simpler? by Anonymous Coward · · Score: 0

      How about an even simpler explanation: the Earth isn't round. As it rotates there will be a "wobble". This means the sattelite "wobbles" with it.

    7. Re:Mayube something simpler? by Anonymous Coward · · Score: 0

      Nonuniformities in the Earth can make a satellite's orbit "wobble", but they can't produce frame-dragging.

  28. Re:Space and time are necessary to define each oth by Anonymous Coward · · Score: 0

    Then can we infer time dilation at the locations on the map (see CNN article) that report high gravity distortion?

    Man, you Democrats will do anything to explain away pre-election poll data

  29. www.finalmentrix.nl by bembem · · Score: 0, Offtopic

    www.finalmentrix.nl

  30. yeah, real sad.... right.... by commodoresloat · · Score: 5, Funny

    it's really a sad state of affairs when a glorified weblog isn't able to report news faster than a multibillion dollar media corporation with reporters stationed all over the globe.

  31. 6 feet = 1.8288 meters by Anonymous Coward · · Score: 4, Funny

    Not to be pedantic, didn't we learn that conversions in spacecraft need to be more precise?

    Sincerely,
    The Mars Climate Orbiter (AC to avoid karma whoring and giving away my location)

    1. Re:6 feet = 1.8288 meters by capnjack41 · · Score: 1

      I thought 1.8288 feet = 6 meters...?

    2. Re:6 feet = 1.8288 meters by iantri · · Score: 1
      I'm curious;

      Why are the conversions even necessary? Is it totally impossible for an American company to build something in metric?

  32. Thanks! by commodoresloat · · Score: 1

    I thought frame dragging was when you dragged the frame of a window with your mouse. I was going to point out how this would never have happened if Earth used a one-button mouse.....

  33. Because I have nothing more constructive to add by An+Onerous+Coward · · Score: 0, Offtopic

    How many years before we all have to drag ourselves off the couch and go out and readjust our satellite dishes?

    --

    You want the truthiness? You can't handle the truthiness!

    1. Re:Because I have nothing more constructive to add by Anonymous Coward · · Score: 0

      off the couch? we pick up the phone which is next to the remote and call someone to do it for us.

  34. Stupid question time... by ArbitraryConstant · · Score: 1

    Is this at all related to that effect where the gravitational influence of the sun is slightly reduced at the point of totality in a solar eclipse?

    I've been vaguely looking around for more information on that. From what I can gather, it's a reproducible observation, but other effects haven't been ruled out, so no one's sure what to make of it.

    --
    I rarely criticize things I don't care about.
  35. Great Ceasar's Ghost! by Anonymous Coward · · Score: 0

    Superman was right, by spinning opposite the earths rotation at super speed you can turn back time!!!

    1. Re:Great Ceasar's Ghost! by Anonymous Coward · · Score: 0

      Does that mean if my washing machine goes backwards my underpants get soiled again?

    2. Re:Great Ceasar's Ghost! by Anonymous Coward · · Score: 0

      Yes, if it spins fast enough.

  36. Re:Space and time are necessary to define each oth by Anonymous Coward · · Score: 0

    That is so funny!
    Mod parent up to warp factor 9.999r!

  37. Nice, BUT... by zombiestomper · · Score: 0, Offtopic

    Where are the flying cars?

    I want my flying car, dammit!

  38. What you be talking bout Willis? by NarrMaster · · Score: 1

    Um, in regards to number 2: Uh, yeah, Earth's gravity does have an effect, the satellites are in orbit. Other Points: I'm sure they've taken atmospheric drag into consideration, and the Moon's and/or Sun's gravity wouldn't have the effect they've measured.

    --
    That's right. All your base.
  39. Disinformative by Anonymous Coward · · Score: 0

    Nature article, 2nd paragraph:

    The experiment, carried out for virtually no cost with Earth-based laser range-finders, scoops Gravity Probe B, the US$700 million orbiting craft launched in April to test exactly the same effect.

  40. Theory? by cbr2702 · · Score: 4, Informative
    No. Not until it's proven. As long as someone could come up with another theory that predicts the exact same results, in a different way, which is not disproven, it's still a theory.

    Newton's laws have not been proved, they are just very likely. And there are some problems with them. So why not extend this naming to relativity?

    I could say "My theory includes everything in General Relativity, except for a small sphere four miles wide in the center of Andromeda, where light travels twice as fast."

    Then while you have a theory that has not been disproved, Ockhams Razor advises us to use the simplest one that explains all the data, and that's not yours.

    Yes, this makes truly proving anything in the physical world basically impossible.

    Which is why it is not a good idea for us to require theories to be "proven" before becoming "natural laws". We call a proven "theory" a "theorem".

    --


    This post written under Gentoo-linux with an SCO IP license.
    1. Re:Theory? by SubliminalLove · · Score: 3, Insightful

      Then while you have a theory that has not been disproved, Ockhams Razor advises us to use the simplest one that explains all the data, and that's not yours.

      You make an excellent point here, but not the one you think you do. Ockham's Razor, as you point out, advises us. It says that the least complicated explanation for observed behaviour is probably the correct one. It does not say that it is definately correct. It simply allows us to predict which of several explanations is most likely to be correct based on our past experience that things are usually simpler rather than more complicated. Ockham's Razor, four thousand years ago, would have had us believe that the stars were little point-sources of light floating just above the clouds. Certainly that was a more simple explanation of our observations than the idea that they were huge self-sustaining fusion reactions happening thousands of light-years across a limitless universe.

      ~Benjamin

    2. Re:Theory? by DavidTC · · Score: 2, Insightful
      That wasn't the simplest explanation. It wasn't an explanation at all.

      The entire universe can be explained by the obvious 'That's the way it is.', but not the simpliest explanation at all, it's just the laziest one.

      --
      If corporations are people, aren't stockholders guilty of slavery?
    3. Re:Theory? by Anonymous Coward · · Score: 2, Interesting

      You make an excellent point here, but not the one you think you do. Ockham's Razor, as you point out, advises us. It says that the least complicated explanation for observed behaviour is probably the correct one. It does not say that it is definately correct. It simply allows us to predict which of several explanations is most likely to be correct based on our past experience that things are usually simpler rather than more complicated.

      Actually, Occam's razor states that explanations should never multiply causes without necessity. When two viable explanations are offered for a phenomenon, the simplest full explanation is preferable. The principle is most often expressed as "entia non sunt multiplicanda praeter necessitatem," or "entities should not be multiplied beyond necessity." William wrote, in Latin, "pluralitas non est ponenda sine neccesitate," which translates literally into English as "plurality should not be posited without necessity." That forms the basis of methodological reductionism, also called parsimony, which I personally don't agree with, because "entities should not be multiplied beyond necessity" is an argument against the existence of higher being, and as such is not falsifiable.

      Also, talking about Occam's razor we should mention Chatton's anti-razor, saying that if three things are not enough to verify an affirmative proposition about things, a fourth must be added, and so on. That forth thing is often God for people who believe in Him. In the philosophy of religion Occam's Razor is often used to challenge arguments for the existence of God and I think that explaining it we should also mention that it is only a hypothesis, especially when many scientists today agree that the universe is (superficially) non-random, so it must have been designed by an intelligent designer. Personally I think that if people in all times and in different places have believed in God, it is unlikely that he does not exist, besides morality cannot exist without God, but I clearly state that it is a matter of my personal opinion. I believe that talking about Occam's razor you should likewise state that it is only your personal belief.

      Ockham's Razor, four thousand years ago, would have had us believe that the stars were little point-sources of light floating just above the clouds.

      Occam's Razor is attributed to the 14th century English logician and Franciscan friar, William of Ockham.

    4. Re:Theory? by Krach42 · · Score: 1

      Ockham's Razor states "do not create entities unnecessarily", not that the simplest explination is best.

      In fact, a simpler explaination of heat would be that there are heat molecules that are passed from one object to the other.

      Ockham's Razor eliminates this because you're making an entity from thin air, without having observed them, and that an existing theory explains the observed phenomena without the need for creating a heat particle.

      I use this same reason to refuse the belief in a graviton until it is shown that it must exist, and that the only explanation available which account for the observed phenomena requires them.

      --

      I am unamerican, and proud of it!
    5. Re:Theory? by mollymoo · · Score: 1
      Then while you have a theory that has not been disproved, Ockhams Razor advises us to use the simplest one that explains all the data, and that's not yours.

      Occam's razor also advises us that the spelling "Occam" is preferable to "Ockham", as it has fewer letters :)

      --
      Chernobyl 'not a wildlife haven' - BBC News
    6. Re:Theory? by scarletire · · Score: 1

      But there is a "heat particle". It's called a photon.

    7. Re:Theory? by servognome · · Score: 1

      But wait the "heat particle" is not only a particle, its a wave! So much for "simple" explainations.

      --
      D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
    8. Re:Theory? by Anonymous Coward · · Score: 0
      I use this same reason to refuse the belief in a graviton until it is shown that it must exist, and that the only explanation available which account for the observed phenomena requires them.
      You and me lil' brudda!

      You refuse to believe in the gravitron, I'll refuse to believe in the psychotron.
    9. Re:Theory? by Anonymous Coward · · Score: 0

      Your mistaking tools for theory here. Occams razor is a method used to form the best possible theories one can. This makes it neither perfect, nor says it will always get the best, or even correct answer.

      It's also not something you can use as an argument against higher beings, unless the higher beings refuse to give any evidence of there existence at all, in which case the obvious answer this tool will give you is, is that if there are no extra factors needed to be able to explain the current universe, that you should then remove the postulate of higher beings until such time that you do find such evidence.
      Gathering any evidence is up to whoever is interested I'd think, as has always seemed to be the case in science. And I believe occams razor is a fairly essential tool for science, because otherwise there would be little to properly keep in check unwanted proliferation of hypothesies.

      As for belief in science, I would point you to the epistemology, which clearly states the thoughts on how you aquire knowledge, and what if anything in it should be considered belief or not. I'm quite happy to work within in which I think are most reasonable constraints, of one of it's subfields, empyrie. Expecially considering it's the only method I know of that has consistently given us new usable knowledge that has benefitted everyone in the end.

      I hope these comments are of some use to you or someone else who might perhaps like to study the matter more in depth and find out why science works the way it is.

      Quickshot

    10. Re:Theory? by Anonymous Coward · · Score: 0

      >>I think that if people in all times and in different places have believed in God, it is unlikely that he does not exist, besides morality cannot exist without God

      wow, you were doing well and then just glibly say 'I believe in God because a lot of other people do'. that has to be the worst argument for belief I've ever heard. there isn't any reason to even begin to give examples of all the idiocies you'd have believed in over history, and how only in the last 2 thousand years or so would you have believed in anything resembling the concept we now call God.

    11. Re:Theory? by Anonymous Coward · · Score: 0

      While in vacuum heat is indeed transported via photons, in solid matter heat is transported via phonons (crystal lattice vibrations). Heat cannot be attributed to just one particle because heat=energy more precise heat="energy distributed over many (or all) degrees of freedom".

    12. Re:Theory? by NoOneInParticular · · Score: 1
      ... is an argument against the existence of higher being, and as such is not falsifiable.

      Not true, theories denying the existence of a higher being are perfectly falsifiable. "There is no God" can be falsified by showing God (maybe in a picture of her or something irrefutable like that). "There is a God", however, cannot be falsified and is therefore not a valid scientific theory.

    13. Re:Theory? by aug24 · · Score: 1

      Occam's razor doesn't say what you said either, actually. Specifically William of Occam didn't even mention using his razor to predict which theories are right. He simply advised against using theories with elements which weren't necessary for the solution to the problem to work, and said that they could be 'cut out'. In other words, don't introduce redundant complexity.

      Justin.

      --
      You're only jealous cos the little penguins are talking to me.
    14. Re:Theory? by scarletire · · Score: 1

      I have to agree that heat is a complicated subject and talking about a "heat particle" is a little silly but the phonon is a bad counter example. A phonon is "a quantized mode of vibration occurring in a rigid crystal lattice" - not a fundamental particle. The lattice itself is governed by electromagnetic interactions. The force carrier for electromagnetic interactions is the photon.

    15. Re:Theory? by stonecypher · · Score: 1

      You two name droppers should probably learn to spell Occam.

      --
      StoneCypher is Full of BS
  41. DOH! by Short+Circuit · · Score: 1

    I missed the "of" ...

    My bad. Sorry.

  42. Frame Dragging & Clipping? by Anonymous Coward · · Score: 0

    Try upgrading the earth to a AMD based system with a liquid cooled NVIDIA card.

  43. Some question that can be answered ? by Mikeybo · · Score: 3, Interesting
    Interesting, 'cause that can help us as new way to look at the space.

    - If the earth's spin warps space around the planet what else is created by others planets or, what's a galaxy's effect arounds or inside itself ?

    - Will this fabric help us to travel farther without a conventional energy ?

    - Is the actual space station fullproof against anykind of fabric ripples ??

    1. Re:Some question that can be answered ? by Tzarius · · Score: 1

      - If the earth's spin warps space around the planet what else is created by others planets or, what's a galaxy's effect arounds or inside itself ?

      It's the same for all objects, from Pluto to the Sun to galaxy clusters.

      - Will this fabric help us to travel farther without a conventional energy ?

      I think you misunderstand - the "fabric" of spacetime is everywhere already, it's comparable to the "ether" in terms of its basic concept. We still require energy to move objects, the 'fabric' cannot be assymetrically affected.

      - Is the actual space station fullproof against anykind of fabric ripples ??

      Ripples in spacetime would require vast amounts of concentrated energy before they would even be noticeable - besides the fact that if anything even remotely destructive enough to cause damaging 'ripples' detonated within the galaxy, the conventional energy released would wipe us out.

  44. Re:Yo mama by NanoGator · · Score: 1

    "Yo mama so fat, she causes a twist in the very fabric of space causing small orbiting objects to shift by 6 feet. take THAT!"

    Yo mama's so fat, she only a donut away from changing the tide!

    --
    "Derp de derp."
  45. In contrast to human laws... by Alwin+Henseler · · Score: 3, Insightful
    ..theories do not become laws by collecting evidence in their favor..

    In contrast to human laws, which just 'become' without any evidence in their favor (and then presented as absolute truths).

    Yes, I've always known that mother nature is far better at creating sensible & logical constructs (and enforcing them)...

    1. Re:In contrast to human laws... by Anonymous Coward · · Score: 0

      Yes, I've always known that mother nature is far better at creating sensible & logical constructs

      However mother nature did create women

    2. Re:In contrast to human laws... by Anonymous Coward · · Score: 0

      Well, it was mother nature after all. Father time clearly didn't do a thing about it.

    3. Re:In contrast to human laws... by Anonymous Coward · · Score: 0

      That's because if he did anything, he would have been wrong, and if he didn't, he'd just be a lazy worthless slob.

  46. Understatement of the year by Nitish · · Score: 5, Funny

    From the CNN article: Black holes [are] typically much more massive than Earth.

  47. Relativity and Einstein on Project Gutenberg by CaptainPinko · · Score: 3, Informative

    I took a course on the philosophy of modern physics at university and on the our text books was Einstein's own called Relativity : the Special and General Theory fairly informative and yet accesible. It is available for free from Project Gutenberg. Just click on the first link.

    --
    Your CPU is not doing anything else, at least do something.
  48. Axioms? by istartedi · · Score: 1

    I thought things that were just accepted as true were called "axioms". Is "law" a synomym for "axiom" or are they different?

    --
    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
    1. Re:Axioms? by HorsePunchKid · · Score: 2, Interesting
      I thought things that were just accepted as true were called "axioms". Is "law" a synomym for "axiom" or are they different?
      "Law" is definitely not a synonym for "axiom". I think the grandparent poster is rather confused. A "law" is not just something that we have observed to be true and then taken for true (i.e. taken to be an axiom). Rather, "law" is a term that has just been loosely applied, suggesting more strength than a "theory", but both pieces of scientific knowledge are not to be considered infallilble or not open to scrutiny. It is true that our scientific "laws" tend to be more fundamental in what they say, but they are still "explanations" in the same way that theories are (contrary to what the grandparent seems to be saying).

      The grandparent has pieces of truth ("theories are never proven true"), but doesn't seem to have it quite right (since laws are never "proven true", either). Hope that helps clarify things. I can address the grandparent post more thoroughly if this post was too vague.

      --
      Steven N. Severinghaus
    2. Re:Axioms? by fucksl4shd0t · · Score: 1

      The grandparent has pieces of truth ("theories are never proven true"), but doesn't seem to have it quite right (since laws are never "proven true", either).

      Go easy on him, will ya? Before posting that he got frame-dragged out of his chair by up to 6 feet (10% margin of error) when his fat mother-in-law walked to the bathroom.

      --
      Like what I said? You might like my music
    3. Re:Axioms? by Too+Much+Noise · · Score: 1

      He does actually have it right. "Laws" are in fact "empirical laws" that are observed to be true in most cases (all cases initially, sometimes experimental refinement shows exceptions[*]). "Theories" are models that have to be able to explain at least the behavior stated by the "laws" (and explain exceptions if they are observed). Take Ohm's law and the theory of transport in metals; Snell's law and the theory of electromagnetism; energy/momentum conservation laws and analytical mechanics (and, from there, quantum mechanics, relativity); Thermodynamics laws and Statistical Mechanics (just to re-list his examples). Laws state the "how"; theories are for the "why".

      [*] As laws admit exceptions, they are definitely not "axioms". They just state that, under certain circumstances, a certain behavior is observed, which might not occur under different circumstances. Example: Coulomb's law breaks down at extremely small distances.

    4. Re:Axioms? by Rufus88 · · Score: 1

      I think the grandparent poster is rather confused.

      Possibly, but I don't think so :).

      A "law" is not just something that we have observed to be true and then taken for true (i.e. taken to be an axiom).

      I did say "observed to be true", but I didn't say "taken for true" or "taken to be an axiom". I agree with you that laws are not axioms. Axioms fall within the domain of philosophy, logic, and mathematics. They are not part of the natural sciences. (Well, that might not be *completely* true. One might accept the internal consistency of the universe to be an axiom: an event cannot be construed to both have occurred and not occurred. But I digress...)

      Rather, "law" is a term that has just been loosely applied,

      I think I kind of implied that, by referring to the law of gravity as "what goes up must come down", and invoking Ohm's law that doesn't hold for everything, but only for devices where resistance is cconstant.

      both pieces of scientific knowledge are not to be considered infallilble or not open to scrutiny. [...] laws are never "proven true", either

      I do not dispute this, nor did I earlier.

    5. Re:Axioms? by Guignol · · Score: 1

      The energy conservaion "law" is however a theorem, proven within the underlying theories

    6. Re:Axioms? by HorsePunchKid · · Score: 1
      Sorry I didn't get back to this sooner. A friend of mine put it in a good way, reasonably concise and useful: A law is something that is provably true inside a theory. This statement contains inside it the apparent strength of a law, while still acknowledging that the law depends on the theory for its scientific validity.

      My problem with your statement, which I failed to articulate clearly, is that such statements tend to contribute to the confusion about the place of "laws" in science. Pseudo-scientists (creationists, intelligent design people, etc.) tend to latch on to this apparent flaw in science (the fact that science requires assumptions and that theories aren't provable) to selectively dismiss whatever claims are contrary to their own beliefs. *sigh*

      Anyway, thanks for clarifying your understanding of the semantics. I think we're pretty much on the same page here :).

      --
      Steven N. Severinghaus
    7. Re:Axioms? by HorsePunchKid · · Score: 1

      See my response here if you're interested. (If only Slashdot/SlashCode had a way of keeping "active" stories visible to the people who have participated in them.)

      --
      Steven N. Severinghaus
  49. Oh Shit... by Farrside · · Score: 1

    There goes the planet!

  50. Re:Yo mama by DJCouchyCouch · · Score: 3, Funny

    My favorite one of all time is: Yo Mama's so fat when she jumps up in the air she gets stuck.

  51. So lemme get this straight... by Powercntrl · · Score: 0

    The reason my frame rate in Doom 3 drags ass isn't because my Radeon 8500 is old & busted, it's the Earth's fault? Stupid Earth, see if I want to save the planet now...

    --

    ---
    DRM is like antifreeze, to the MPAA/RIAA it's sweet, to the consumers it's poison.
  52. Gravity Probe B readout date? by andrewagill · · Score: 1

    Does anyone know when the critical moment of readout will come for Gravity Probe B? It was sent up in April, but how long before it completes its mission? (And is the readout going to be what do you get when you multiply six by nine?)

  53. Thank god for Einstein! by Anonymous Coward · · Score: 0

    He's also the reason the sky is blue, if you didn't know... From the nature article:

    The space warp is a consequence of Einstein's general theory of relativity...

    1. Re:Thank god for Einstein! by Anonymous Coward · · Score: 0

      yeah, he is another example that a college degree is a useless piece of paper only loved by morons and idiots.

      Almost every Genius in this world was shunned hard by his teachers so he had to go it alone to discover the secrets that the fools at the universities are too blind to see.

      so yes, I flip off every higher degree holder

  54. Wrong by bluGill · · Score: 1

    When your margin of error is 10%, 6 feet = 1 meters. You are making the common freshman mistake of using more digits than are significant.

    1. Re:Wrong by vondo · · Score: 2, Insightful

      That's two meters, of course, but you're right. On the other hand, it may be that the distance dragged is known more accurately than that but that the prediction is only accurate to 10%. But, I doubt it. (I haven't read the FA.)

  55. could it be something else by austad · · Score: 3, Interesting

    Could it be something else that they haven't thought of? Like possibly due to inductive friction caused by the interaction of earth's magnetic field and non-ferrous metals in these satellites?

    --
    Need Free Juniper/NetScreen Support? JuniperForum
  56. It's that stretching thing... by rmdyer · · Score: 4, Insightful

    As a long time science buff I'm pretty well read on the various "big" theories out there relating to how the universe works. Your explanation is a good one, and tends to follow the standard space-time is a fabric, blah, blah, blah. But the things that annoy me most about modern concepts are the big ambiguities that result of some simple explanations. For example, take the concept of the "stretching" of space-time. If we up all the dimensions by 1, going from a flat sheet to a volume. We would expect that the word "stretching" doesn't fit very well. We alrady have 3 dimensions of space and 1 of time. So basically what stetching means in 3 dimensional terms is "densities" of space. More precisely we find that when large masses are placed in a space-time fabric (volume) the space around it gets more dense. If space is more "dense" around large masses then that means there is "more space" within a given volume. But what volume? Gravity waves would be seen as simply variaitions in the densities of space-time.

    This all seems very strange until you read up on some of the modern concepts of vacum physics. Space is not seen as being emtpy at all. Space is actually something. Where matter within space is simply some strange configuration of whatever space is. This is sort of like ice in water, where water can be viewed as space, and ice is the matter within it. If this is true, as in the way things actually work, then everything that exists is really just one thing...the stuff that space is made of. Apparently though, this "stuff" is non-continuous, becuase how can you stretch it otherwise? It seems to have a finiteness so that, like air pressure, it gets more dense the closer you get to a massive object. In my view, the Bekenstein bound, a model for the granularity of quantum events, seems to be linked to the finiteness of space-time. The Bekenstein bound proposes that any given volume of space can only have a finite number of states. This brings about the model of a computer screen where you only have a certain number of pixels within a given area. To expand further, based on the Bekenstien bound, it would be only possible to have a finite number of physical manifestations (objects) within a given volume of space-time. In the same way, you can only have a limited number of possible pictures viewable on a computer screen within a given resolution.

    Does the universe actually work this way? If it does, then this suggests the possiblity that the volume of the entire universe is a large finite state machine. Within the lifetime of the universe, the machine is working out all the possible logical permutations of reality as time progresses. What we don't know is: Is the volume of the entire universe infinite? What would be the end result of the permutations?

    The contrary argument would be that space-time could actually be continuous, but that there only exists so-called quantum interfaces at a certain level. Below the level of the interfaces, we cannot know about any of the other features of space-time. The interfaces block further exploration into space-time because our measuring devices only operate at the level of the interfaces. This model is very much like working with Legos(TM). Legos blocks are finite, and they allow you to build large numbers of possible devices (objects) within a given volume of space. But Legos can only interact at the connection level. Where there are no connections, Legos cannot be known.

    The more I read, the more I'm finding that modern science is telling the above story over and over again as we come to understand things better. Do you guys read the same picture, or am I just reading the wrong books?

    +1

    1. Re:It's that stretching thing... by greenguy · · Score: 1

      More precisely we find that when large masses are placed in a space-time fabric (volume) the space around it gets more dense. If space is more "dense" around large masses then that means there is "more space" within a given volume. But what volume? Gravity waves would be seen as simply variaitions in the densities of space-time.

      I get that. Mostly. I see how that applies to astronomical figures. What I don't see is how the variations in the densities of space-time make my pencil fall off my desk. Please help me.

      This is a serious question.

      --
      What if I do the same thing, and I do get different results?
    2. Re:It's that stretching thing... by slaida1 · · Score: 1
      Ya, I'm getting the same(ish) picture: we're like running programs in a machine trying to probe the pattern of the memory hardware cells/transistors where we and and our own world is stored and being executed. Seems like those "transistors", looking like calabi-yau spaces can have quite a bit more states than 1 and 0.

      Maybe alchemists were right after all trying to make gold from other stuff.. now, we need a method to control the states of these transistors and crack possible error correction mechanisms that would otherwise "fix" our changes in planck time.

      --
      Preserve old classics: copy your collection onto all hard drives.
  57. A Sheet Of Paper and a Weight? by sweatyboatman · · Score: 2, Insightful

    Your example with the sheet of paper presupposes an outside force that causes the objects on the paper to slide towards the depression. To wit, um, gravity.

    Without the force of gravity all the objects would remain where they were, regardless of the deformation of the paper. They wouldn't even stay on the paper, they would just float.

    I know there's real, valid science behind relativity. I just would like to request a better metaphor. Or a better explanation. Or maybe just a turkey sandwich.

    That is all

    -tom

    --
    It breaks my pluginses, my precious!
    1. Re:A Sheet Of Paper and a Weight? by esanbock · · Score: 1

      That metaphor explains the how. You're looking for a metaphor that explains the why. Why the fabric of space and time warps in the first place. Maybe those quack string theorists have an "answer".

  58. Inertia by CustomDesigned · · Score: 2, Informative
    The planet causes a depression. Why would the moon move into the depression? Something must be pulling it down - the simple existence of a depression would not cause the moon to move (that is, if you reject gravity as the pull between bodies).

    The moon doesn't move into the depression. The moon , like every other object, keeps traveling in a straight line until it collides with something. All the depression does is change the shape of a straight line. Any object in "free fall" is travelling in a straight line through curved space. Yes, satellites in orbit are falling unhindered in a straight line - that looks like a circle due to the curvature of space.

  59. The Laws Of Relativity? by Pan+T.+Hose · · Score: 2, Funny

    Isn't it time soon...to change from 'theory' it to The Laws Of Relativity?

    I don't think so. Legislation is not the answer to every problem.

    --
    Sincerely,
    Pan Tarhei Hosé, PhD.
    "Homo sum et cogito ergo odi profanum vulgus et libido."
  60. Excellent! Mod parent up! by rmdyer · · Score: 1

    Your explanations are eloquent in the prose! I could not have said it better myself.

    I only have one thing that may make what you are saying sharper. When you ask the question of "why" you are actually looking for "intent". Do the things we observe in the universe require "intent"? This may be the million dollar question, as in, the question that the Hitch Hikers Guide to the Galaxy tries to come up with. If phenomenon in the universe do not require intent, then that means that gods are now dethroned. If a thing can exist by itself, on its own in an evolutionary way for the entire history of the universe (even if continuous), then what other explanations are required?

    +1

  61. Slide towards the Weight? by weston · · Score: 1

    Well think about a sheet stretched out very flat. On this sheeta are a number of very light objects. Now think of a lead weight placed in the center of the sheet. The sheet will bend into an inverted cone shape and all the items will slide towards the weight.

    Slide towards the weight? Dragged by what, gravity?

    I suppose now you're going to tell me what exactly is waving when I work out all those particle-wave functions....

  62. Gravitational non-uniformity of a black hole? by Theovon · · Score: 2, Interesting

    So, apparently, they had to take into account the non-uniformity of the earth's gravity in order to make accurate measurements. Turning that around, the non-uniformity of the earth's gravity caused a corresponding non-uniformity in the frame-dragging of the satelites.

    Consider measuring the non-uniformity of frame-dragging of a black hole. If there is any, that would imply a non-uniformity in the matter in the black hole. Through this, we can determine something about the nature or distribution of the matter inside of the black hole, even though we cannot directly observe it (without being spaghettied).

    So, you CAN get information back out of a black hole after all! (Although string theory already tells us that.)

    1. Re:Gravitational non-uniformity of a black hole? by Anonymous Coward · · Score: 0

      No, you can't use this to get information out of a black hole. Black holes can be non-uniform, but all we can measure is the non-uniformity of the horizon, which tells us about the non-uniformity of the matter at the time it crossed the horizon. It tells us nothing about what's going on with the matter inside the black hole.

  63. Space has a Fabric by Anonymous Coward · · Score: 0

    You all realize that space "twisting" means that there actually is "something" to space. It actually exists as opposed to there being a true vacuum

  64. Re:A Brief Explanation -- a better analogy by InterGuru · · Score: 4, Insightful
    The analogy of a weight on a stretched membrane is easy to visualize, but depends on a force outside the "fabric" of space - ordinary gravity.



    A better analogy on how curved space can seem like a force is to look at two ships, both some distance apart at the equator heading north. For the sake of this argument, assume the Earth is totally cloud covered, and those on the surface are not aware of anything off of the surface.



    The captains will see that their initial motion is parallel. They are both going in a straight line, along a longitude line, heading for the North Pole. On the surface of a sphere, as on any curved ( or uncurved) space, a straight line is defined as the shortest distance between two points. As the two ships head north, the captains will notice that they are getting closer to each other; finally colliding at the Pole.



    After scratching their heads to figure out what happened, the will conclude that there was some force drawing the two ships together. From "outside" we can see that the collision was caused by the curvature of their space, but those whose motion, and vision is confined to the surface of a sphere, will give this force a name. Perhaps "gravity."

  65. Several misconceptions by Pan+T.+Hose · · Score: 2, Informative

    Most of people in this thread seem to be very confused, so please let me explain the most basic terms, using the most relevant quotes taken from several Wikipædia articles.

    Axiom in epistemology is a self-evident truth upon which other knowledge must rest, from which other knowledge is built up. To say the least, not all epistemologists agree that any axioms, understood in that sense, exist.

    Axioms in mathematics are not self-evident truths. They are of two different kinds: logical axioms and non-logical axioms. Axiomatic reasoning is today most widely used in mathematics.

    The word axiom comes from the Greek word axioma, which means that which is deemed worthy or fit or that which is considered self-evident. The word comes from axioein, meaning to deem worthy, which in turn comes from axios, meaning worthy. Among the philosophers of the ancient Greeks an axiom was a claim which could be seen to be true without any need for proof.

    Laws of logic and mathematics describe the nature of rational thought.

    Law of nature or physical law in science is a statement that describes regular or patterned relationships among observable phenomena. It is a scientific generalization based on empirical observations. Laws of nature are conclusions drawn from, or hypotheses confirmed by, scientific experiments. The production of a summary description of nature in the form of such laws is the fundamental aim of science. Laws of nature are distinct from legal code and religious Law, and should not be confused with the concept of natural law.

    Often, those who understand the mathematics and concepts well enough to understand the essence of the physical laws also feel that they possess an inherent intellectual beauty. Many scientists state that they use their perception of this beauty as a guide in in developing hypotheses, since there seems to be a connection between beauty and truth.

    Physical laws are distinguished from scientific theories by their simplicity. Scientific theories have many of the same properties as laws, but are generally more complex than laws; they have many component parts, and are more likely to change as the body of availabe experimental data and analysis develops.

    Theory in mathematics is a set of statements closed under logical implication. In mathematical logic, "theory" is the term for a set of well-formed formulae consisting of certain axioms and all theorems provable from said axioms. Gödel's incompleteness theorem states that no theory (formalized using a consistent set of axioms in First-order logic), that defines the concept of natural numbers, can include all true statements.

    Theory in sciences is a model or framework for understanding. In physics, the term theory generally is taken to mean mathematical framework derived from a small set of basic principles capable of producing experimental predictions for a given category of physical systems. An example would be "electromagnetic theory", which is usually taken to be synonymous with classical electromagnetism, the specific results of which can be derived from Maxwell's equations.

    The term theoretical to describe certain phenomena often indicates that a particular result has been predicted by theory but has not yet been observed. For example, until recently, black holes were considered theoretical. It is not uncommon in the history of physics for theory to produce such predictions that are later confirmed by experiment, but failed predictions do occur. Conversely, at any time in the study of physics, there can also be confirmed experimental results which are not yet explained by theory.

    For a given body of theory to be considered part of established knowledge, it is usually necessary for the theory to characterize a critical experiment, that

    --
    Sincerely,
    Pan Tarhei Hosé, PhD.
    "Homo sum et cogito ergo odi profanum vulgus et libido."
  66. I hate it when that happens by trick-knee · · Score: 1


    the very fabric of space is twisted by our whirling world.

    yes, this world gets my knickers in a knot sometimes as well.

  67. Disagree by mbrod · · Score: 0

    I have to disagree that the rotation of the earth is causing this effect. The same amount of mass would cause this distortion regardless of its' movement.

    1. Re:Disagree by mollymoo · · Score: 1
      I have to disagree that the rotation of the earth is causing this effect. The same amount of mass would cause this distortion regardless of its' movement.

      You are of course free to think whatever you like, but unless you come up with a better theory everyone will carry on using the stuff Einstein et al. came up with because, as accurately as we can measure, it's right. Simply saying "I disagree" doesn't get you far in science.

      --
      Chernobyl 'not a wildlife haven' - BBC News
    2. Re:Disagree by mbrod · · Score: 1

      Well with General Relativity Einstein looks at in terms of a "frame" of reference where if the body is rotating in it you observe a curvature of space and time due to this.

      With Teleparallelism it looks at the effect in terms of "flat" space instead of curved space.

      I look at in terms of the energy and thus matter that is in a given space distorts the very fabric of space and time thus yielding the effect we call gravity and many other observable things. I don't see anywhere in either theory an expanation why rotation is needed to explain this effect nor why it would have to be. Although in the observable universe all bodies we would encouter would be rotating in relation to at least something else, so it is the norm.

      So maybe someone who is more expert at the details of the theories can right me if I am wrong that the rotation qualifier is not actually needed nor correct?

    3. Re:Disagree by meringuoid · · Score: 1
      Rotation is absolute, not relative. Get on a roundabout - it's spinning and you know it's spinning without reference to anything external, because you can feel the centrifugal and Coriolis forces.

      The metric of spacetime around a nonrotating, spherically symmetric body is the Schwarzschild metric, which has no frame dragging. Around a rotating body it is the Kerr metric, which has all sorts of exciting effects in it. For instance, a rotating black hole has a region called the ergosphere, just outside the event horizon, where nothing can ever be stationary because space itself is being dragged around so rapidly. AFAICT, what has been detected here is the small difference between the Schwarzschild metric and the Kerr metric, where bodies orbiting the Earth are concerned.

      Rotation can make a big difference in relativity. The distortion of spacetime is a result of the mass-energy of a body, but the shape of that distortion is affected by its rotation.

      --
      Real Daleks don't climb stairs - they level the building.
  68. This happened on my PC too. by Maul · · Score: 1, Funny

    I got frame dragging when playing Doom 3, so I updated to a GeForce 6800. The planet just needs to do something similar.

    --

    "You spoony bard!" -Tellah

  69. Because the rubber sheet's an inexact metaphor by Beryllium+Sphere(tm) · · Score: 2
    >Why would the moon move into the depression? Something must be pulling it down - the simple existence of a depression would not cause the moon to move (that is, if you reject gravity as the pull between bodies).

    You're thinking too deeply for the popular metaphor, which is for use by people who don't want to think deeply.

    Here's a better metaphor, but still stopping short of the math. I've asked a PhD general relativist for commments: he didn't seem happy but had no direct objections.

    Imagine the upper surface of your glass of Coke. The bubbles pucker the water around them. The bubbles tend to fall together and stick together. It's the water's springiness that's forcing them together: the water is "seeking" the configuration where it is least strained by the total amount of puckering.

    Think of objects as bubbles of carbon dioxide, the dimples around them as their gravity fields, and the Universe as a vast glass of Coca-Cola :-)

  70. Spin Doctorates by Doc+Ruby · · Score: 1

    I remember reading about an experiment proposed some years ago to test rotational gravitational attenuation. The idea was that spinning masses reduce their effective mass attraction with other masses. So a selfcontained experiment was due to be launched on a US Space Shuttle. After entering orbital microgravity/micropressure, a calibrated mass would be raised within a chamber lined with "gravity detectors": other masses attached to tension sensors, attracted by the test mass, if I recall correctly. Then the mass would be electromagnetically spun, accelerated to an appreciable percentage of lightspeed in angular velocity. The theory predicts that the sensors would measure the spinning mass gravitational attraction lowering as it spun faster.

    Was I completely tricked by some pseudorelativity? Or was this experiment performed? Did the mass reduce?

    --

    --
    make install -not war

    1. Re:Spin Doctorates by krysith · · Score: 1

      I'm afraid I haven't heard of the experiment you described, but you may find the article "Swimming in Spacetime", by J. Wisdom, Science 2003 Mar 21 interesting. It addresses the possible change in motion caused by distortions or spinning of a body in a curved spacetime (gravitational field).

      The effects calculated by Dr. Wisdom (what a great name!) are very small, but I believe that they could be increased to measurable quantities by changing the model used from a distorting mode to a very radidly spinning mode.

    2. Re:Spin Doctorates by Doc+Ruby · · Score: 1

      So I'm correct in remembering that relativity predicts that apparent mass ("gravitational attraction") decreases with angular velocity. That's counterintuitive at mesoscale and low energy - gyroscopes seem heavier. I wonder whether we can accelerate nanoparticles to high sub-c speeds in MRI alternating fields, and measure their reduced mass. Quantum dots tagged with attached ions might be cheap enough, and transmit reliably enough, to run an accurate experiment on Earth without sending up a Shuttle - especially in the newly mapped Earth gravity field. Of course, if it works, we could replace the Shuttle with spinning, flying saucers...

      --

      --
      make install -not war

  71. great, another term to abuse on star trek by fulana_lover · · Score: 3, Funny

    wanna bet the next few episodes of star trek enterprise are gonna talk about how "the frame dragging around us is warping the space time continuum!" it'll probably be the nazis fault too...

  72. Whew! by Reteo+Varala · · Score: 1

    A quick skim over the subject had me thinking that the "satellite" was the moon, and it was being pulled 6 inches closer to the earth by a twist in the fabric of space..

    Instead, I go to an article, and end up feeling like the aforementioned twist is in the space between my ears.

    I gotta go grab me some tylenol now...

  73. Those who moderated parent as Troll by temojen · · Score: 1

    Please refer to grandparent post for context.

  74. Alright mr smarty pants.. by Anonymous Coward · · Score: 0

    bla bla bla, look at me, I'm literate...bla bla bla I have a college education...

    pfffffffffffffffff...

    "every day like a queen on her thrown"

    Batman stricks again...

    1. Re:Alright mr smarty pants.. by Anonymous Coward · · Score: 0

      Mr A.Coward, the troll?

      Atleast I hope for you it's just that.

    2. Re:Alright mr smarty pants.. by Kiryat+Malachi · · Score: 1

      I like math enough to lecture about it in real life, why wouldn't I bitchslap a /.er when they're wrong?

      Bla bla bla, I'm smarter than you... not difficult.

      --

      ---
      Mod me down, you fucking twits. Go ahead. I dare you.
      (I read with sigs off.)
  75. Read up on string theory. by Anonymous Coward · · Score: 1, Informative

    Somewhere, General Relativity must break down so that it can match up with wherever Quantum Mechanics breaks down, permitting the two theories to be joined in some coherent fashion.

    Read up on string theory. Neither GR nor QM must "break down" to join them together. But science makes progress by assuming that existing theory is always improvable, so a search for where existing theory fails will continue as long as science continues. But the math of strings that combines GR and QM does not break either like Newton's laws which ARE broken by both GR and QM.

    1. Re:Read up on string theory. by Rob+Carr · · Score: 1
      Read up on string theory. Neither GR nor QM must "break down" to join them together.

      There's areas where the current equations no longer work as they are currently formulated. That's "break down" in the same way that Newton breaks down at high velocities and in other places.

      I've done a bit more than "read up" on string theory. I've actually worked with some of the equations to get a feel for what one model was proposing. I do wish I'd paid more attention in the post-calculus math classes I took.

      --
      This sig seemed like a good idea at the time....
  76. wtf? by mrselfdestrukt · · Score: 0, Troll

    Oh, And I thought that god dude created the universe... No, I didn't actually.*ducks*

    --
    "I used to have that really cool,funny sig ,but it got stolen."
  77. In Capitalist America... by Anonymous Coward · · Score: 0

    ...the Earth drags YOU!

  78. Missing links by nounderscores · · Score: 1

    This article by Yasuko Onuma et al Univeristy of Tokyo shows how grossly different physical traits come about by small changes to sequence within key genes.

    Pretty much what Onuma's team did was take the gene sequence that encodes a gene that bosses other genes around from a fly and stuck it in a frog. Now the frog has a compound eye with multiple lenses.

    Of course, over evolutionary time you wouldn't need Onuma to do this, random mutagenesis could do it just fine. If there was an advantage to having compound eyes for frogs, then that frog would be populous and be easily found, along side their normal eyed ancestors (for a while at least).

    The evidence of such missing link animals wouldn't show up on the fossil record - if you had a frog which could - at the change of a few base pairs in its DNA - form a compound eye, but the backup gene was working so they just had regular eyes, it's gross morphology would look like a regular frog when you dug it up.

    For life to live and have kids, it has to work. You can have animals that have "half a circulatory system" (like flies which lack lungs but instead have an "open" circulatory system where blood mixes with air) but generally these look like fully fledged morphologyies because they work so well.

    Exciting evolutionary events tend to happen at the molecular scale, and don't manifest until everything is ready.

    Watch your children.

  79. Re:Yo mama by nacturation · · Score: 1

    Yo mama's so fat, we're all inside her right now!

    --
    Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
  80. Well, for starters... by pjt33 · · Score: 1

    You and they alike are confusing accuracy with precision. In terms of single numbers (rather than number-plus-error-margin) precision corresponds to the number of significant digits and accuracy corresponds to the number which are correct.

  81. The universe can be discrete, but not "lego" by RedLaggedTeut · · Score: 1

    Instead of thinking about Lego Blocks for the universe, I think that it is better to imagine that the start of the universe looks much like a fractal of the kind which looks like a plant.

    The nodes are the elementary particles(like quarks, electrons, muon, lepton-neutrinos), and the branches/lines connecting the nodes are forces/relationships between particles.

    Particles would generate more and more interactions between them, based on some rules which define proximity in space.

    I guess you would need to have some removal or at least aging/recoloring of lines to define movement, I must admit I haven't thought about this part.

    The Lorentz contraction would be the result of overloading the otherwise fair processing of events by concentrating too many events around too few particles, e.g. black holes and maybe slower speed of light in dense mediums. This would mean that you can generate relativity effects not only by gravity, but by concentrating other physical events in an area in spacetime. Maybe could be seen in these laser-powered fusion reactors. Or maybe you couldn't ever verify that theory because there are gazillion more gravity nodes/"particles" than other particles/"light" nodes.

    --
    I'm still trying to figure out what people mean by 'social skills' here.
  82. Plagiarism again by 192939495969798999 · · Score: 1

    Stop copying the AP wire and not crediting them. That's plagiarism, everyone.

    --
    stuff |
  83. Re:Yo mama by Anonymous Coward · · Score: 0

    Yo mama's so fat, she's on both sides of the family.

  84. huh? by DeathByDuke · · Score: 1

    99% of predicted drag with a error of 10% anyone else confused by that?

  85. cool and then ... lagragian points by Anonymous Coward · · Score: 1, Interesting

    so how those this affect the lagrangian points?
    will a object at lagragian point say between earth
    and the moon start spinning because of this?
    can we somehow :) make energy from this?

  86. Fat people at the fair ground by Anonymous Coward · · Score: 1, Funny

    This just confirms what I've always known - that very fat people should not be allowed on fair ground rides that spin very quickly.

  87. Hogwash by Anonymous Coward · · Score: 0
    especially when many scientists today agree that the universe is (superficially) non-random
    Unless you can cite some statistics which support this (that many scientists believe...) I can bullshit.

    morality cannot exist without God,


    Morality can exist purely as a trait which improves chances of procreation (and hence servival of the species).
  88. Not So Brief ! by salec · · Score: 1

    A "slide" would mean that you have the force of gravity perpendicular to the sheet, which is absurd.

    This elastic sheet analogy is used only to ilustrate how linear non-accelerated movement suffers inclination in vicinity of a massive body (roll smaller spheres in trajectories passing near more massive/more sheet-twisting bodies, and see how they change their path).

    To understand the observed attracting force to objects apparently "at rest", one should also take into account movement of said objects along the time axis.

  89. Re:Yo mama by Anonymous Coward · · Score: 0

    Your momma's so fat, her blood type is Ragu(TM).

  90. Hmm... by mpdolan37 · · Score: 1

    I wonder if you can predict presidential elections by using this data.

    --
    Facts are useless, they can be used to prove anything.
  91. Re:Yo mama by bheerssen · · Score: 1
    Phppt! The Pharcyde said it best:
    Your mom is so fat!
    How fat is she?
    Your mom is so big and fat
    that we hopped up on her back
    to get some burgers from Wendy's,
    but her skates went flat!
    I got stuck in her butt crack!
    They thought I was lost
    but I saved by the g-strap.

    I said your mom!

    (Your mom's got snake skin teeth.)

    --
    (Score: -1, Stupid)
  92. Re:Yo mama by shpoffo · · Score: 1

    That would imply your mother is the Earth , which would be true in everyone's case. (and when you think about it - not that insulting of thing to say =)

    .
    -shpoffo

  93. Mu by Anonymous Coward · · Score: 0

    The way I see it, the problem is inside the question. You keep asking "why", but have you thought about the meaning of the question and its implications?

    For a "why" to be answered, there must be a being with free will who makes something _for a purpose_. That's an absolutely anthropocentric way of seeing the problem. You are taking for granted that things only happen when "somebody" does them, and this "somebody" does have a purpose in mind.

    Tell me, what makes you think that apart from our cultural heritage? We are _so_ used to be surrounded by people that it's hard for us to understand that not everything happens because "somebody" wanted to do it.

    The sky is blue. Is it really needed that it's blue _for a purpose_? it might be blue just because the laws of physics happened to be like this in this universe. No "why", really. Just because.

    Radioactivity is a random process. Imagine that an isotope has just fissionated. Would you ask yourself "why"? is it a reasonable question? or can we be satisfied with the notion that it's a random process?

    Sorry, just rambling :) I did enjoy your posts quite a lot.

  94. Every 10 years my slashdot my name means something by EinsteinWasRight · · Score: 1

    Saw this late but couldn't resist.

  95. Re:Time travel (Mod parent up. Pretty please.) by Dulimano · · Score: 1

    Please mod parent UP. This is the most insightful remark on time travel I have ever read. And I read a lot. 808140, please recommend some further reading. :)

  96. Re:Yo mama by Anonymous Coward · · Score: 0

    "your mother is the Earth , which would be true in everyone's case."

    The earth is not my mother, it is a creation of my Father.

  97. You call THIS morality?! by Anonymous Coward · · Score: 0

    Grandparent: morality cannot exist without God

    You: Morality can exist purely as a trait which improves chances of procreation (and hence servival of the species).

    You have just proved the point raised by the grandparent. By your "logic" rape is clearly moral. But God says:

    Thou shalt not covet thy neighbor's house, thou shalt not covet thy neighbor's wife, not his manservant, not his maidservant, nor his ox, nor his ass, nor any thing that is thy neighbor's

    So please tell me, who is more moral? I seriously fail to understand how anyone could make relativists like yourself moral if not by threatening them with eternal torture, and then sending them straight to Hell. I just cannot express how outraged I am when people like you present apotheosis of rape and sodomy. Do you also think that murdering unborn babies is good when the pregnancy is dangerous for the mother? I suppose you do, since the death of the mother wouldn't be advantageous for the survival of "the species" as you keep calling humanity.

    1. Re:You call THIS morality?! by Anonymous Coward · · Score: 0
      Different AC here...


      By your "logic" rape is clearly moral.


      That doesn't follow; rape doesn't necessarily increase the propagation of one's genes ... not if potential rapists know they will be imprisoned, exiled, killed, etc.

      But in any case, only the most extreme social Darwinists base their morals on such claims. Being a moral relativist merely means that you don't think there is an absolute source of morals; it doesn't say anything about how individual moral relativists arrive at their moral codes. (It's usually not sociobiology.)

      [stuff about coveting]
      So please tell me, who is more moral?


      Personally, I don't think there's anything immoral about coveting. It's not necessarily a nice personality trait, but it's not immoral either.


      I seriously fail to understand how anyone could make relativists like yourself moral if not by threatening them with eternal torture, and then sending them straight to Hell.


      Sorry, it appears to be the theists who need threats of eternal torture to keep them in line; if God didn't tell them what to do, they wouldn't have any other absolute source of morals to tell them what was right or wrong. Moral relativists don't require any such source, and manage quite fine.


      I am when people like you present apotheosis of rape and sodomy.


      "Apotheosis" of rape and sodomy? "Elevation to divine status"? I don't understand what you're saying. Do you just mean to say "condone"?

      Rape is coercive and immoral. Sodomy between consensual adults -- fine and dandy, as far as I'm concerned.


      Do you also think that murdering unborn babies is good when the pregnancy is dangerous for the mother?


      Well, plenty of people don't consider abortion to be murder, period. But even of those who do, if it's a choice to be made between the life of the mother and the life of the child ... well, there are always lousy situations in which somebody has to die and you have to choose who, and it's not at all obvious that (as you appear to feel) the child's life is the one that must have precedence. If you feel that abortion is murder, no, it's not good to murder an unborn baby, but it's also not good to murder a living woman, so tough: you have to do one or the other. (Unless you consider doing nothing and allowing the mother to die to not constitute murder.)
    2. Re:You call THIS morality?! by Anonymous Coward · · Score: 0

      I wrote: By your "logic" rape is clearly moral.

      You wrote: That doesn't follow; rape doesn't necessarily increase the propagation of one's genes ... not if potential rapists know they will be imprisoned, exiled, killed, etc.

      So it is moral when a raper is a good strategist who manages to fertilize more women than he otherwise would be able to procreate with? You confuse morality with selfishness. You sound like a satanist.

      You wrote: But in any case, only the most extreme social Darwinists base their morals on such claims. Being a moral relativist merely means that you don't think there is an absolute source of morals; it doesn't say anything about how individual moral relativists arrive at their moral codes.

      But if you don't have an absolute source of morals, does it mean that you can change those morals whenever you please? Remember that morals are not always convenient, nor they are immediately advantageous, or otherwise we wouldn't need them.

      You wrote: Personally, I don't think there's anything immoral about coveting. It's not necessarily a nice personality trait, but it's not immoral either.

      Personally, someone might not think there's anything immoral about raping a child, and in fact many perverts don't think what they do is immoral. Would you let them rape children because they don't think there's anything immoral about it? Would you?

      You wrote: Sorry, it appears to be the theists who need threats of eternal torture to keep them in line; if God didn't tell them what to do, they wouldn't have any other absolute source of morals to tell them what was right or wrong. Moral relativists don't require any such source, and manage quite fine.

      You are correct. They wouldn't have any other absolute source of morals. They wouldn't, but unlike you they do.

      You wrote: Rape is coercive and immoral. Sodomy between consensual adults -- fine and dandy, as far as I'm concerned.

      Many people find rape "fine and dandy". But of course, their arbitrary opinion is wrong, while yours is right? That is exactly why we need an absolute source of morals.

      You wrote: there are always lousy situations in which somebody has to die and you have to choose who, and it's not at all obvious that (as you appear to feel) the child's life is the one that must have precedence.

      There is a very important problem you seem to overlook, namely the original sin. It is passed through each generation of human being by the act of intercourse, because it affects the physical and material nature of man. A baby who have a soul but whose sins have not been forgiven during the ritual of baptism cannot attain salvation. An unborn baby has zero chance of being baptized. A mother has non-zero chance of being baptized, so in other words there is a slight chance that the mother will avoid eternal damnation for unredeemed sin. This chance in the case of unborn baby is zero. I hope you will now understand the position of people who believe in God.

    3. Re:You call THIS morality?! by Anonymous Coward · · Score: 0

      So it is moral when a raper is a good strategist who manages to fertilize more women than he otherwise would be able to procreate with? You confuse morality with selfishness. You sound like a satanist.

      No, you dumbass. I never said that I agreed with social-Darwinistic morality. I just said that your argument was wrong, which it was -- even under a morality that says that "propagating the species is good", rape is not necessarily moral. (It may be sometimes moral, as you pointed out.)

      Incidentally, Satanists generally wouldn't agree that rape is moral, either. Not that you know any Satanists, I'm sure.

      But if you don't have an absolute source of morals, does it mean that you can change those morals whenever you please?

      Yes. That's one of the strengths of moral relativism: it allows for personal growth. It also allows for rationalization. But, for that matter, so does moral absolutism. Such is life.

      Remember that morals are not always convenient, nor they are immediately advantageous, or otherwise we wouldn't need them.

      So what? If I see a nice car, I can't just convince myself that it's all right to just steal it, regardless of whether it would be convenient or advantageous to do so. Most people can't either. Some people might, but they can do that if they're moral absolutists, too. More likely, they just ignore the moral issue altogether.

      You are correct. They wouldn't have any other absolute source of morals. They wouldn't, but unlike you they do.

      That's why their morality is inferior. Moral relativists have morals regardless of whether someone tells them what's wrong. Moral absolutists don't.

      Many people find rape "fine and dandy".

      No, not very many do.

      But of course, their arbitrary opinion is wrong, while yours is right?

      I think that my opinion is right, so I feel free to act upon it. I fully recognize that a rapist might think that he's right, and he might think that his moral system is better than mine. But since I think he's wrong, and I think my moral system is better than his -- otherwise, I'd adopt his -- I'm going to act on my moral code when reaching opinions on the morality of his actions, or decisions on whether he should be punished. In fact, so do you: you realize that somebody else might have a moral code than the one you think is right, but that doesn't sway your decision-making, does it?

      Moral relativism doesn't mean acknowledging that all moral opinions are right! The whole point of a moral code is to decide what is right and what is wrong. The fact that different people have different codes doesn't change the fact that any given person, with any given code, has opinions on what is right or wrong -- regardless of whether their moral code is absolute or not.

      That is exactly why we need an absolute source of morals.

      This, of course, is nonsense, for many reasons.

      First, moral absolutism or moral relativism has little to do with whether one actually commits crimes. There are plenty of theistic rapists out there too, you know. Rapists don't rape women because they think it's right. If you ask a rapist whether he thinks rape is moral, he generally won't say yes -- regardless of whether he's a moral absolutist or relativist. He just doesn't care that it's wrong.

      Likewise, it doesn't take a moral relativist to rationalize decisions away. I hate to invoke Godwin, but there were plenty of Nazi Christians -- devout, even. They just managed to convince themselves that killing was okay, if it was applied to Jews.

      In reality, a moral relativist is no more likely to rationalize away morality than is a moral absolutist. It doesn't matt

    4. Re:You call THIS morality?! by Anonymous Coward · · Score: 0

      Incidentally, your link regarding "raping children" refers to the legal definition of rape; as the link states, the moral definition is rather more ambiguous. If both parties consent to sexual activity, it's not necessarily rape. Generally, most people will add the proviso that the consent be between mentally competent individuals, and will argue that children aren't mentally competent to consent.

      Regardless, as I stated previously, whether I'd let them have sex with children, or call it "rape", or call them "perverts", has nothing to do with what they think on the matter.

    5. Re:You call THIS morality?! by Anonymous Coward · · Score: 0

      You wrote: No, you dumbass. I never said that I agreed with social-Darwinistic morality. I just said that your argument was wrong, which it was -- even under a morality that says that "propagating the species is good", rape is not necessarily moral. (It may be sometimes moral, as you pointed out.) Incidentally, Satanists generally wouldn't agree that rape is moral, either. Not that you know any Satanists, I'm sure.

      I've read the The Satanic Bible. I think it's enough. Please don't call me "dumbass" unless you want to sound like an infantile moron who uses vulgar invectives whenever he cannot form an intelligent argument.

      You wrote: So what? If I see a nice car, I can't just convince myself that it's all right to just steal it, regardless of whether it would be convenient or advantageous to do so. Most people can't either. Some people might, but they can do that if they're moral absolutists, too. More likely, they just ignore the moral issue altogether.

      Thou shalt not steal! Clear and simple. Can you see a pattern already?

      I wrote: Many people find rape "fine and dandy".

      You wrote: No, not very many do.

      Oh, so now it's argumentum ad populum, right? It's a logical fallacy.

      You wrote: I think that my opinion is right, so I feel free to act upon it. I fully recognize that a rapist might think that he's right, and he might think that his moral system is better than mine. But since I think he's wrong, and I think my moral system is better than his -- otherwise, I'd adopt his -- I'm going to act on my moral code when reaching opinions on the morality of his actions, or decisions on whether he should be punished. In fact, so do you: you realize that somebody else might have a moral code than the one you think is right, but that doesn't sway your decision-making, does it? Moral relativism doesn't mean acknowledging that all moral opinions are right! The whole point of a moral code is to decide what is right and what is wrong. The fact that different people have different codes doesn't change the fact that any given person, with any given code, has opinions on what is right or wrong -- regardless of whether their moral code is absolute or not.

      The statement "all is relative" is either a relative statement or an absolute one. If it is relative, then this statement does not rule out absolutes. If the statement is absolute, on the other hand, then it provides an example of an absolute statement, proving that not all truths are relative. You can reply to that by saying that only one thing in the world is absolute: relativism. It solves this dilemma. Or does it? It says that my argument is correct in a way. Not all statements are relative, but the only statement that is not relative is a statement "The only thing that is absolute is that all things are relative." But does it preserve relativism for all intents and purposes? No. It inevitably introduces absolutism. As you can clearly see, true relativism leads to paradoxes.

      You wrote: Also, if you want to argue that absolute morals must come from God, we can also get into the Euthyphro dilemma and divine command theory: is, say, murder wrong because God commands it? Or does God command us not to murder because murder is wrong? If the latter, then God's will is irrelevant to the morality of one's actions. If the former, then morality is arbitrary -- whether or not God does decree something to be moral, God can decree that anything can be moral -- and there's little reason to care about God's moral goodness.

      This is a very insightful question. Murder is wrong because God commands it. It is better explained on the example of the first, more important commandment:

      You shall have no other gods before me. [...] you shall not bow down to them or serve them; for I the LORD your God am a jealous God, visiting the iniquity of the fathers upon the children to the third and fourth generation of those who hate me, but showing steadfast love to thousands

  98. Those physics-wizards at CNN by DrKyle · · Score: 1

    Specifically, the new results can be applied to black hole theory. In fact, it is with black holes -- typically much more massive than Earth -- that some of the first signs of frame dragging were spotted.

    Wow, Black Holes are typically more massive than Earth? Which ones aren't? the black holes made by digging in the dirt?

  99. Doesn't this invalidate Michaelson-Morley? by orichter · · Score: 1

    The real question I have regarding this is that if we can drag space (our frame) along with us, doesn't that mean that Michaelson-Morley is invalid (i.e. isn't this another explaination of why we don't see any fringe pattern?) Does this in fact mean that light may in fact travel at different speeds in different reference frames?

    1. Re:Doesn't this invalidate Michaelson-Morley? by Anonymous Coward · · Score: 0

      Frame-dragging isn't the same thing as aether drag. Aether drag can account for Michelson-Morley, but fails other observational tests, such as stellar aberration. Frame-dragging doesn't affect M-M very much.

      The speed of light is constant in any inertial frame. (It doesn't have to be constant in non-inertial frames; see, for instance the Sagnac effect.)

  100. Re:Yo mama by stonecypher · · Score: 1

    Yo momma so fat her n-tier topological brane has its own zip code.

    --
    StoneCypher is Full of BS
  101. Maybe? by Anonymous Coward · · Score: 0

    Maybe those near-Earth objects had their orbits altered by the tremendous sucking action coming from Washington state?

  102. Just wondering... by Anonymous Coward · · Score: 0
    That's why 99% +/- 0.01% is better for science than 99% +/- 10%

    How the fuck do you know what's good for science?

    I'm not the grandparent of this post (that guy didn't care enough to help you pry your head out) and I posted this AC because the replies are likely to be morons who really can't get it and I don't care for responding to those.

    Perhaps you're the moron? Seems to be begging the question a bit.

  103. Re:A Brief Explanation - how/why by one-of-many · · Score: 1

    I've often thought of how and why in the same way you describe. How focuses on the mechanism or manner of cause/effect. Why focuses on the motive or intent of cause/effect.

    I checked three dictionaries and none drew a clear line, citing the word "reason" in both. I wish the distinction was more accepted.

    I wonder if the difference is clearer in other languages. There is a concept of Dependent Origination. In a book, the Dali Lama used this concept to suggest that eastern thought does not focus on one cause, but rather multiple conditions required for effect.

    Some links I looked at in forming a response:

    http://en.wikipedia.org/wiki/Causality
    http://w ww.m-w.com/cgi-bin/dictionary?book=Diction ary&va=mechanism&x=0&y=0
    http://www.m-w.com/cgi-b in/dictionary?book=Diction ary&va=how&x=0&y=0

    http://en.wikipedia.org/wiki/Pratitya-samutpada# Ge neral_formulations
    http://en.wikipedia.org/wiki/B uddhist_philosophy#D ependent_Origination

  104. Re:Yo mama by Anonymous Coward · · Score: 0

    I was going to try to put it intelligently, but succint wins:

    Fuck you.

  105. Occam's razor by cbr2702 · · Score: 1
    While I did misquote Occam's idea, it still can prove the point I wanted. The GP said:

    I could say "My theory includes everything in General Relativity, except for a small sphere four miles wide in the center of Andromeda, where light travels twice as fast."

    The point was that the GP's "small sphere" was an "element which [wasn't] necessary for the solution to the problem to work" and so should "be 'cut out'"

    --


    This post written under Gentoo-linux with an SCO IP license.
  106. Re:Yo mama by Anonymous Coward · · Score: 0
    succint wins

    It funny that you would misspell a word that implies "clear and precise expression."