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Science

Speed of Light Inconstant? 592

Posted by michael from the still-can-count-on-death-and-taxes dept.
DHR writes "Australian scientists have discovered that light isn't quite as fast as it used to be." We've done previous stories on these findings. Those of you with subscriptions to Nature can read the actual paper, the rest of us will just have to suffer.
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Speed of Light Inconstant? More

Speed of Light Inconstant?

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  • ObTrek Reference (Score:5, Funny)

    by Amazing Quantum Man ( 458715 ) on Wednesday August 07, 2002 @05:44PM (#4028580) Homepage
    So, does that explain the ever changing warp scale in Star Trek?
    • Not necessarily... depends on the frame of reference, whether the Klingons or the Romulans are watching. But did you know that physicists are actually working on a warp drive [arxiv.org] (at least theoretically)? :-)

      Even constantly improving the model [arxiv.org]!

  • Hmmm.. (Score:5, Funny)

    by Anonvmous Coward ( 589068 ) on Wednesday August 07, 2002 @05:47PM (#4028599)
    I've noticed it takes a while for flourescent lightbulbs to turn on. I guess all of the technology bloat has finally taken a noticable performance hit on light.

    • Re:Hmmm.. (Score:3, Funny)

      by letxa2000 ( 215841 )
      When 20 billion light years you reach, move as fast you will not!

    • I'm a Lightwave animator, so spare me the 'Linux will solve all your problems' crap.

      I guess you'll have to work a bit slower, then, or risk exhausting the light waves you have left to work with. (-:

      Linux seems to have solved problems for ILM, Pixar, DreamWorks, yadda yadda... but Disney, now there's an interesting contrast of priorities: they render on Linux with one hand, and legislate against it with the other. Maybe it's one of those light-side/dark-side things. Dr Linux and Mr RIAA, sort of.

  • ...cause my exam in Algorithm Construction is only two days away, and I _really_ could use some extra time =)

  • Entropy and the collapsing universe theory. (Score:3, Interesting)

    by GodInHell ( 258915 ) on Wednesday August 07, 2002 @05:48PM (#4028610) Homepage
    Would this perhaps be linked to the idea that there's a limited amount of energy in the universe, which is more and more being turned into kinnetic potential as objects get further and further from the center point?

    Or perhaps we're just setting aside another 'unbreakable' barrier.

    -GiH
  • the rest of us will just have to suffer.

    And given our new knowledge about changes in the speed of light, you'll suffer a little more slowly then you are used to.

  • Australian scientists (Score:5, Funny)

    by Jonny Ringo ( 444580 ) on Wednesday August 07, 2002 @05:50PM (#4028624)
    eh their mate, thats not a light.

    Now that's a light.
    • Honestly, its sentences like this where it really matters if you use "there" vs "their."

      I honestly thought, the first few times I read it, that it was referring to somebody's mate, like girlfriend or wife, as opposed to "hey there, mate, that's not a light ... now that's a light."

  • I think I've found proof using empirical research (Score:5, Funny)

    by jukal ( 523582 ) on Wednesday August 07, 2002 @05:52PM (#4028647) Journal
    > "That's illegal. It would be like a cup of coffee sitting on your desk getting hotter," Lineweaver says

    Placing a coffee cup on top of my laptop and running Microsoft Outlook provides the exactly same effect. Where can I get my Nobel prize?
  • Beginning of article:

    In October, 1971, American physicists took four super-accurate atomic clocks, kept two on the ground and put two on commercial jets flying at 1000 kmh in opposite directions around Earth.
    When the planes landed, the scientists found what they were hoping for: The clocks on the high-speed journeys were ticking a few billionths of a second behind their stationary friends.

    Isn't the speed of a jet negligible compared to the speed of the Earth rotating, revolving around the sun, the sun revolving around the center of the galaxy and the galaxy spiralling in the expansion of the universe?

    Please explain.

  • E=mc^2? (Score:2, Interesting)

    by InsaneCats ( 583788 )
    So if the speed of light is slowing down, could we convert matter to energy, wait millions of years for the speed of light to change, and then convert it back - violating the conservation of energy laws?

    • Re:E=mc^2? (Score:3, Interesting)

      by rknop ( 240417 )

      So if the speed of light is slowing down, could we convert matter to energy, wait millions of years for the speed of light to change, and then convert it back - violating the conservation of energy laws?

      Good question, but I would think probably not. E=mc^2 doesn't really tell you about some remarkable physical process that lets you convert between two differen things "mass" and "energy". Mass is just another form of energy, and that equation tells you how much energy you have in (say) one kilogram of mass.

      I'd have to think harder whether or not there is a problem with conservation of energy here. Here's the challenge: come up with a thought experiment that lets you get "something for nothing" from a changing speed of light. Just counting the energy in the universe isn't good enough (see below); what you need is some way of increasing (say) the stored energy in a localized object or particle *without* introducing any energy or work from outside. I can't think of a way to do it, but maybe somebody else might. (I haven't really posed my thought experiment well; can somebody suggest a better way to pose it?)

      The reason that just talking about the total energy in the universe isn't good enough is that in fact General Relativity already does *not* have a global law of conservation of energy! There is a *local* conservation of energy, which is expressed in terms of derivatives of the stress-energy tensor. However, the fact that there is no single global inertial reference frame for the whole universe makes it difficult to say what is the "energy of the universe".

      You can come up with things that look like they violate conservation of energy with plain vanilla GR and cosmology right now. For instance, the cosmological redshift. Start with a universe that has one photon in it. The universe expands, and the photon redshifts. Now the photon has less energy. What happened to conservation of energy? Similarly, if you have a cosmological constant (vacuum energy), and your universe gets bigger, you have more vacuum, thus more energy. What happened to the conservation of energy? With an infinite universe you can always say that you're pushing work out to further and further reaches of the universe, and since you never reach an "edge" you don't have to worry about somebody ever having to absorb all that work. (With a closed universe, I believe that formally some of the energy goes into the curvature.) But, really, conservation of energy is a local concept in a GR rather than a universe-wide concept.

      -Rob

  • We will have to suffer doubly (Score:4, Funny)

    by JudgeFurious ( 455868 ) on Wednesday August 07, 2002 @05:56PM (#4028674)
    Since most of us don't have the subscription I deduce that the majority of replies will come from AC's and be composed of nonsense.

  • An old poke at physicists. (Score:5, Funny)

    by DarkHelmet ( 120004 ) <mark&seventhcycle,net> on Wednesday August 07, 2002 @05:56PM (#4028676) Homepage
    I'm reminded of an old joke one of my math professors used to tell me.

    There were a group of people in a room of different professions, and a theorem was put forth onto the board that stated that all Odd Numbers Are Prime. Each person was supposed to disprove this.

    The mathematician started off by looking at each number.

    1, 3, 5, 7, 9.... 9 is not prime, the theorem is false.

    The social worker turned in a long sheet of paper going "2 is prime, 4 is prime, 6 is prime..." etc.

    The physicist turned in the following:

    1... 3... 5... 7... 9 (Experimental Error), 11, 13.....

    • 1 is not a prime number. look it up.

    • One and Primes (Score:2, Informative)

      by chrislike ( 134650 )
      This is from the top of my head, and as such, may have some errors, especially dates.

      Now that that disclaimer is done with ... there are more reasons to think of One as prime that there are to not, and the primary reason to think of it as a non-prime, non-composite integer is one more of practical value than mathematical correctness.

      You see, the Fundamental Theorem of Algebra says, briefly, that every number can be reduced to a unique, finite, multiplicative set of prime numbers.

      Now, if one were prime, we would run into the terrible, horrible problem of this being false. And all mathematics would slowly fall with it. Because if one were prime, one would be equal to:
      1 x 1
      1 x 1 x 1
      1 x 1 x 1 x 1 ...
      et all.

      However, before the 1800's or so, one was in fact considered to be a prime number -- as math was not then a practical discipline. At all. And it was considered prime because, from a theoretical standpoint, it is, as it only has the factors of itself and one. Nowhere did it then say that those must be unique factors.

      anyway, just thought I'd shed some light, given the posts on top of posts that are a bit off on what it is to be prime.

    • Another poke at physicists - from a chemist (Score:4, Funny)

      by WIAKywbfatw ( 307557 ) on Wednesday August 07, 2002 @09:03PM (#4029830) Journal
      This one came from my old chemistry teacher:

      A philosopher, a mathematician and a physicist are at one end of a very, very long room. An observer tells them that there's a bottle of fine whisky on a table at the other end of the room, and that they can take as many leaps as they like to get to the other side and claim the prize but that every step must cover half the remaining distance, no more, no less.

      The philosopher stands still, and contemplates whether or not the table and the whisky are there at all.

      The mathematician does some quick thinking, and works out that he can never really reach the table as there will always be a finite distance, no matter how small, left to cover. He too stands his ground.

      The physicist sets off across the room. He makes one, two, three, four jumps until he's withing arm's length of the table, shouts "that's close enough!" and grabs the bottle for himself.

      (And after all that, what did I go on to do at university? Yep, astrophysics. Part astronomy, part physics, part mathematics and, at least with the options I took, part philosophy. No wonder I'm not a scientist by profession any more.)

  • Possibilities? (Score:5, Interesting)

    by yeoua ( 86835 ) on Wednesday August 07, 2002 @06:00PM (#4028712)
    One possibility, though, is that the structure of the vacuum in space has changed. This is where we get into the rather spooky world of quantum physics. When light travels through a medium other than a vacuum, such as glass or water, it slows down. A vacuum, far from being empty, is teeming with quantum "virtual" particles that flit in and out of existence.

    Sometimes those particles become real, such as under a strong electric charge, Lineweaver says. If the vacuum of space is changing uniformly across the universe, just as the universe is expanding uniformly, it could affect the speed of light.

    Well... this was the hypothesis that was given in the article... and from the looks of this, it seems that there is a possibility that light didn't slow down at all. Here he explains that it is the medium that light is travelling in that is slowing it down. So light's top speed in a vacuum may still be the same... c, but the medium, the universe, is changing. Who knows.

    But if light is slowing down, then that faster than light travel maybe possible. However, how the hell do you see anything when your going faster than any signal? Well... maybe you can communicate with the spooky particles and get instant communication while travelling at faster than light speeds. Of course you'd best be sure your data arrived promptly, as you'll never see the planet you just rammed.

  • Not surprising (Score:3, Funny)

    by ucblockhead ( 63650 ) on Wednesday August 07, 2002 @06:01PM (#4028719) Homepage Journal
    Must of us slow down as we get old.

  • Nothing's like it used to be (Score:5, Funny)

    by wrinkledshirt ( 228541 ) on Wednesday August 07, 2002 @06:01PM (#4028725) Homepage
    Back in my day, light was blimblamming all over the place! We had GOOD light in those days. Yessiree, you couldn't go outside with your onion strapped to your belt (as was the fashion at the time) without getting knocked over by rays of light all the time! Not like today's LAZY light, mind you.

  • Dr. Walt Brown agrees with the idea (Score:3, Interesting)

    by danpbrowning ( 149453 ) on Wednesday August 07, 2002 @06:02PM (#4028731)
    This is exactly the case put forward by Dr. Walt Brown (Ph. D.) [creationscience.com].
    • "The universe is only 6000 years old, and as one of the supporting pieces of evidence, here's some measurements from something that's 15 billion years old."

      He's about as deserving of the Doctor title as Doctor Nick Riviera
    • Except that Dr. Brown wants to use the idea to disprove the theory of evolution. The amount that the speed of light would need to change to be of any use to creation "science" (which is about as far from scientific as you can get) is orders of magnitude higher than what's been detected here.
    • What's interesting to me is the uniformly violent reaction of the "educated" crowd to creation scientists (e.g. read a few of the above posts). I'll admit they somewhat deserve it because of their history of intolerance and quackery but they have been correct about a number of things, many of which are still to be discovered.

      Take for example the BS theories of evolution that were passed around as fact until recently. You know, the ones that said that evolution happens at a very slow rate. Creationists argued against this for years because of the nature of how fossils are created. Evolutionists finally caught on and now almost all the recent theories talk about periods of very rapid evolution.

      It's true that a lot of what they're saying is shit. But its also true that traditional scientists are full of it too. All I'm asking is that before you blast it out of the water as religious ranting, consider that they probably have a much more critical view of accepted science than you. Consider whether you what to be the one defending the status quo.

      You should read Dr. Brown's 20 questions for evolutionists [creationscience.com]. No true scientist can read the traditional "irreducible complexities" (like the Bombardier Beetle) without questioning current theories of evolution.

  • Hold your horses.. (Score:3, Insightful)

    by k98sven ( 324383 ) on Wednesday August 07, 2002 @06:05PM (#4028756) Journal
    Well, let's see here:
    The speed of light -is- always constant in one sense,
    simply because the length of 1 meter is defined by the distance light travels in a set time.

    Now, from a more physical standpoint: We need more evidence.
    Quite a few measurements of c have been done, and a single measurement isn't about to upend all this.
    Extraordinary claims require extraordinary evidence, remember?
    Now, nobody says that relativity is a complete and final theory. It probably isn't. But you still need lots
    of evidence to replace it with another theory.
    Otherwise, we won't even know if the theory we're replacing it with is better!

    It's an interesting theory and experiment, but even so, I'd bet on this being a
    freak result, for the simple reason that scientific breakthroughs don't come around that often.

    • The speed of light -is- always constant in one sense, simply because the length of 1 meter is defined by the distance light travels in a set time.

      I believe you've actually hit a very subtle nail right on the head, here, related to string theory. This principle becomes even more important if you look back in time to the Big Bang:

      Disclaimer: I am not a physicist

      Basically, imagine that you're running time backwards, and watching the Big Bang in reverse. As you get closer to time 0, the universe "shrinks" in size towards a radius of the Planck length R. But as it does so, photons (actually, all particles) start behaving differently.

      Radius R=1 is where the weirdness happens: photons in a universe of radius n*R (n>1) resemble completely different particles in a corresponding universe of radius 1/(n*R), but they look more and more like each other as the radius drops to exactly R, where (from the perspective of string theory's winding/vibrational energies), they are identical... and as the radius drops to below R, they change places. Each now has the characteristics of the other.

      It gets weirder: a universe of radius n*R is indistinguishable from a universe of radius 1/(n*R), since "radius" is a length, and "length" measurements (e.g., "one light year") depend on what you define as the "photon".

      What makes this cool is that, from one perspective, there can be no "Big Crunch" where the universe collapses to a point: the universe can never shrink "smaller" than radius R, because once it does, it "really" is getting larger again [as measured by the photon's twin particle]. I believe this is called the "Big Bounce" theory.

      Ok, there were probably a lot of mistakes above, but I think that's the gist of it. So, I'm not surprised to hear that light might have behaved differently when the universe was a slightly-smaller size.

  • the reporting is way off base. and does not match the findings. do refer to: http://www.math.ucr.edu/home/baez/constants.html the fine structure constant is considered more fundamental then speed of light. and it has more than one component, namely: e^2/(hbar*c) so it could be any of the four. it could be that the electric charge used to be smaller, or that hbar is larger.
  • Read this. [slashdot.org]

    I had an argument (well, flame war on his part) with an astronomer about the age of the universe. I told him it has no age becuase the speed of light IS NOT constant and the universe recycles itself. In fact, I told him that the momentum of the universe was slowing down. He told me I was an idiot. These aussies seem to have proved me right.

    Read astronomer-ego flames here, [slashdot.org] as I craftily use my flame proof shield (made of dragon scales no less). I love denting the armor of 'Accepted Scientific Models'.

    • "I love denting the armor of 'Accepted Scientific Models'."

      Great. Now go see about denting a bra. Heh. :D

    • So you're saying your "belief," based upon nothing more than your ideal model of the universe and "proven" by precisely one set of data, should be taken seriously by a professional astronomer?

      He didn't even flame you. Your idea is fine--as the basis for a religion--but there's nothing scientific about it. And if he's anything like other astronomers I've met, his tolerance for pseudo-sceintific bullshit is arbitrarily close to zero.

  • In other news... (Score:3, Funny)

    by sam_handelman ( 519767 ) <samuel...handelman@@@gmail...com> on Wednesday August 07, 2002 @06:10PM (#4028797) Journal
    Planck's constant (h) increased in value this morning to roughly 50 joule-seconds, sending the DJIA to a 95% confidence interval between 0 and 15,000, and increasing the wavelength of a penny moving at a brisk walk to a value on the order of it's own diameter, so that macroscopic, every day objects behave as waves instead of billiard balls. Tennis players in central park (whose velocity could velocity could not be determined as of this printing) may have been alarmed to find tennis balls which hit their rackets were defracted and created interference patterns on the fence behind, instead of going into the opposing court.
  • You will need to set a timer on the light switch so that it switches on 10 minutes before you get up in the mornings.

    Of course, this could be an invaluable application of Asimov's famous chemical which reacted before it was placed in the water. That way the light switch could sense that you wanted the light turned on in 10 mins. and flip the switch ahead of time for you...
  • With Light 3.0, things were plenty fast enough. Even with Light 3.11. Then we moved to Light95 and suddenly things were getting slow. Light98 made it worse still.

    Currently, with LightXP, things are pretty rough. But still, at least they're better than they were under LightME where even the people running OpenSound projects were faster.

    Fortunately, Intel are coming out with new five-dimensional universe technology this fall, so we should be able to upgrade.

  • Must've installed SP3 (Score:5, Funny)

    by Snafoo ( 38566 ) on Wednesday August 07, 2002 @06:17PM (#4028845) Homepage
    (this should be in caps, but, hey, the /. dummy filter would complain.)

    Supplemental End User License Agreement("Supplemental EULA") ...

    * God reserves the right to increase, decrease, remove or otherwise alter 'constants', including, but not limited to, pi, e, the speed of light, and the mean time between bowel movements in any biological organism.

    * Disclaimer of Warranties. To the maximum extent permitted by universal ("a priori") law, God and His suppliers provide you with existence (and any support services, if any) as-is. God and His suppliers hereby disclaim, with respect to any adjustment of constants, perceived or real, all warranties and conditions, whether expressed or implied, and may not be held responsible for any damages, including but not limited to collapsed dimensions, squared circles, invalidated proofs, isolated extraplanetary colonies, and ruined romances, originary in such adjustments. Thank you, have a nice life.

  • In Scientific American, in the late fifties or (Score:4, Insightful)

    by dpbsmith ( 263124 ) on Wednesday August 07, 2002 @06:19PM (#4028852) Homepage
    early sixties, I am almost sure I recall that there was an article showing that the speed of light was changing... decreasing, I believe... there were a number of graphs of various historical determinations of the speed of light, with error bars and everything, with a declining straight line fitted to them.

    • Extensive discussion here [ldolphin.org], no graphs, but even with generous error bars a decrease is statistically very certain.

      As to the `straight line' bit, I'm not sure that there's enough data yet to draw one, and I would expect it to trend more like a decaying exponential anyway.

      There is more extensive discussion here [ldolphin.org] with many graphs including a curve I'm more comfortable with than a straight line. For various reasons I suspect that their curve has too early a start, but it's a good shot, clearly illustrates the principles, and the discussion around it is informative.

      Oh, and you don't need to pay or even register in order to look at it.

  • Again? (Score:5, Insightful)

    by rdslater596 ( 472943 ) on Wednesday August 07, 2002 @06:19PM (#4028856)
    These guys need to cut it out. Its already known in physics communities that the fine structure constant talked about in the article changes when you go to extremely small scales and high energies. However, these guys infer that when the fine structure constant changes the speed of light changes (being one of the items derived from the fine structure constant). No one makes that kind of assertion when the fine strucutre constant changes when dealing with particle physics--instead they extend the theory (by further investigiation) to incorporate the changes. The do not make claims like the speed of light is changing until they actually measure the speed of light! They say the fine strucutre constant has changed and we need more money to investigate what is going on ;-)

    These guys are not DIRECTLY measureing the speed of light. The are measuring a second item and then using that to infer the speed of light has changed. There could be a great deal more going on, so any claims are VERY premature.
  • Given the reputation of the aussies [satirewire.com], this all makes perfect sense. Light slowing down? yeah.. sure...


  • On the one hand they say, about breaking the Second Law of Thermodynamics,

    "That's illegal. It would be like a cup of coffee sitting on your desk getting hotter," Lineweaver says.

    But on the other hand, the article says
    "The discovery means faster-than-light travel, which is prohibited by the law of relativity, may one day be possible. It also changes our understanding of the beginnings of the universe. "

    So why is it that breaking the Second Law of Thermodynamics is so illegal but faster-than-light travel is not? Maybe the Second Law of Thermodynamics is wrong.

    They did get one thing right, though:
    "On the other hand, science is made out of iconoclasm. If old theories never got overthrown, we'd all be out of work. So it's always nice to have something that challenges the basic paradigm and this does so with a vengeance."

    Unfortunately, overthrowing theories is not an everyday occurrence. And I don't quite understand how experimentation is better at proving things than good old mathematics.

    • Unfortunately, overthrowing theories is not an everyday occurrence. And I don't quite understand how experimentation is better at proving things than good old mathematics.

      From the point of view of the physicist, "good old mathematics" is just a tool. All you can prove with mathematics is mathematical theorems. You can't prove anything about the physical universe without some input that comes in the form of either a theory (i.e. base assumptions) about the univesre, or prior experiments and observations you are extrapolating.

      When it comes to knowing something about the universe, experiment and observation are the only way to prove that youre theory is right. Given some observations and a theory you believe, you can use good old mathematics to "prove" other things, but if you perform an experiment that contradicts it, and you make sure the experiment is right (i.e. no errors, no systematic effects you haven't accounted for), then the "good old mathematics" is out the window. Well, not really. Really, the mathematics themselves are fine; it's the theory you started with before cranking the mathematics that is out the window.

      -Rob

    • And I don't quite understand how experimentation is better at proving things than good old mathematics.

      You're missing a key to the usage of mathematics in physics, and that is the magical invocation of a "premise". First we begin with a set of premises. Special Relativity depends on the premise that the speed of light is constant for all observers. Everything derived in Special Relativity, including the imaginary mass for objects going faster than light, rests on the premises of Special Relativity. It would be difficult to challenge the mathematics used to derive Special Relativity, that has been checked and rechecked. If the results of the theory are going to be challenged, it essentially requires a challenge of the premises, showing that there is some exception to the premise that from what we can see, seems to usually be right.

      If the speed of light were shown to be different under different observations, this would mean that Special Relativity would need modification, and thus might open up a theoretical window permitting faster than light travel.

      With that said, hold your breath and wait for a more rigorous measurement method done by independent groups to confirm or refute these results and their interpretation.
  • The researchers were just using surplus arthur anderson computers to crunch the numbers for them. Add in the out of work arthur anderson employees hired as lab technicians and I think we may have figured out what is going on here...

  • Speed of light and time (Score:3, Insightful)

    by nuggz ( 69912 ) on Wednesday August 07, 2002 @06:37PM (#4028970) Homepage
    Interesting they suggest that time and motion are different between two frames of reference travelling at different speeds.

    Isn't this kinda the idea of relativity? How does it change the speed of light?

  • The vacuum energy density of the early universe was much higher. I suspect that this is the cause of their results...

    Time to dust off my old quantum mechanics texts...

  • The second law of thermodynamics is just a statistical consequence of more fundamental laws of physics. I don't see why breaking it is automatically "illegal", while messing with the speed of light is fair game. You get temporal paradoxes if the speed of light is not the same everywhere[1], and that bothers me far more than cups of coffee getting hotter.

    [1] General relativity rules out the concept of "everywhere at the same time", so if the speed of light changes, it can't change uniformly, because there's no uniform.

  • Ok, I'm not a physics major and I didn't get that good a grade back in high school. So I have a few questions, all which may be considered stupid by others who knows stuff... but ok. So go ahead and laugh before you reply ;-)

    The discovery means faster-than-light travel, which is prohibited by the law of relativity, may one day be possible.

    Why would this mean that faster than light travel will (or might) be possible in the future? Why not today? From what they are saying, the speed of light may have slowed down ever since the Big Bang. For me, that means that as soon as the speed of light has decreased, it should be possible with faster than light speed, right?

    If the speed of light was close to infinity, immediately after the Big Bang, [...]

    How close to infinity can one be? When are you far from infinite speed and when are you close? "Almost infinite"? What do they mean here?

    The photons [...] interact with the electrons in the gas clouds, charged particles that orbit the nuclei of the metal atoms. This leaves a fingerprint on the light as it arrives on Earth, called the fine structure constant, Murphy explains.

    How can this be a constant? Is it a universal constant or a constant different for each object? Still, how can this fingerprint be constant?

    Thanks.

    • Re:questions (Score:3, Informative)

      by Peter T Ermit ( 577444 )
      You shouldn't take popular press versions of science papers literally; often the reporter has no more understanding of physics than you do. That being said...

      The discovery means faster-than-light travel, which is prohibited by the law of relativity, may one day be possible.
      I think this is an error on the reporter's part. I don't see how this is at all related to the paper, unless the reporter thinks: "Speed of light changing therefore Einstein was wrong... Einstein was wrong, therefore we can travel faster than light."

      If the speed of light was close to infinity, immediately after the Big Bang,
      Again, a problem with the reporter here. "Close to infinity" means nothing. What this probably means is that the further back you travel in time, the bigger the speed of light was, and as you approach the Big Bang, the speed of light goes off to infinity. A physicist would say that the speed of light diverges, rather than saying it gets close to infinity.

      The photons [...] interact with the electrons in the gas clouds, charged particles that orbit the nuclei of the metal atoms. This leaves a fingerprint on the light as it arrives on Earth, called the fine structure constant, Murphy explains.
      This is actually close to correct, though it's misleading. The fine structure constant equals 2(pi)e^2/hc (if I recall correctly) where e is the charge of the electron, h is the Planck constant, and c is the speed of light. The value of that constant is related to the electromagnetic force, which, in turn, affects the spacing of the lines in an element's spectrum. Conversely, by looking at the spacing of the lines in elements' spectra, you can figure out the fine structure constant.

    • Yeah that picture thing...whew! Took me by surprise.

  • I actually read the paper... (Score:5, Informative)

    by Peter T Ermit ( 577444 ) on Wednesday August 07, 2002 @07:14PM (#4029254)
    ... and it adds absolutely nothing to the argument over whether there are time-changing constants.

    As other people have pointed out, the fine-structure-constant-is-changing work came out a year ago. The fine structure constant is a function of the speed of light, c, and the charge of the electron, e.

    This particular article argues that e can't change much over time without causing inconsistencies, so they conclude that c must have been changing. No new data, no new support for the constant-is-changing theory. (And the original study was pretty damn flawed. This paper isn't bad.)

  • Okay, Science,
    In 10 billion years, take my DNA, clone me, and reconstruct my mind from a computer backup, and when the process is complete, let me know your final answers that you've hopefully really figured out by then:

    Actual Speed of light, and whether it varies.
    Actual color of the universe.
    Actual age of the universe.
    Actual origin of the Earth's moon.
    Whether we're descended from apes.
    What's the nature of human consciousness.
    Whether God actually exists or not.
    Whether cholesterol is good or bad for you.
    Whether global warming is caused by humans.
    Whether gun control increases crime rates.
    Whether fair-use causes loss of revenue.
    Whether flouride causes or cures tooth decay.
    Whether there is an actual speed limit for the x86 architecture that isn't eventually overcome by some new hack.
    Whether security through obscurity really works.
    Whether phenomenology is bunk.

    (etc. ad nauseum)


  • Speed of Light Inconstant? no not really we are just moving faster and faster and light is ....well staying the say as our measurement is relative to us.....

    Haven't you noticed the days get shorter as you get older?
  • That is almost as crazy as the dude on the street corner who held up a sign saying that the ASCII code is going to undergo a fundimental shift. Thta is crazy! No onf jt hpjoh up cfmjfwf uifn/
  • Article quote:

    "Mathematically, there were two possible reasons for this - either the electric charge of the electrons had increased, or the speed of light had fallen.

    Using Stephen Hawking's formula for black hole thermodynamics, Davies, Davis and Lineweaver ruled out the electric charge possibility. By adapting Hawking's formula, they determined that an increase in electric charge would break the second law of thermodynamics, which says energy can only flow from hot spots to cold spots.

    "That's illegal. It would be like a cup of coffee sitting on your desk getting hotter," Lineweaver says.

    Observation -- but didn't they just prove that something "illegal" -- that the constant speed of light is changing -- is actually happening? Perhaps they should examine their logic on this point, because it seems to me it could be either. Or perhaps I should read the original article, where they probably address this issue.

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