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Science

One Hundred Years of E=MC2 408

Eric Ward writes "To mark the one hundredth anniversary of Einstein's famous equation, E=mc2, NOVA has gone live this month with a Web site that features exclusive content and podcasts from ten of the worlds top physicists. This once-in-a-lifetime gathering of top scientists such as S. James Gates, Jr., Brian Greene, Neil deGrasse Tyson and Nobel Laureate Sheldon Glashow simplify what the equation means to our world today and the effect it has had on their careers. NOVA online also details how Einstein grappled with the implications of his revolutionary theory of relativity and came to a startling conclusion: that mass and energy are one, related by the formula E=mc2. Viewers will also find lesson plans through the award-winning NOVA Teacher's Guide and a special library resource kit."
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One Hundred Years of E=MC2

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  • by G4from128k ( 686170 ) on Thursday August 18, 2005 @04:12PM (#13350470)
    Einstein's work showed that Newton's equations were a good approximation for low velocities, but not for velocities approaching c. What if Einstein's work is an approximation, too. Perhaps we will discover that the E deviates from mc^2 when temperatures are very high or very low or m is very large or magnetic fields are especially strong.

    Newton's 3 laws survived 239 years, I wonder how long Einstein's will last?
  • Re:Plagiarist? (Score:5, Interesting)

    by Frymaster ( 171343 ) on Thursday August 18, 2005 @04:20PM (#13350544) Homepage Journal
    my question is, then, why aren't we celebrating another famous 1905 paper by a. einstein? i am, of course, talking about his work on brownian motion.

    einstein was awarded the nobel prize for his brownian paper. relativity, published the same year, was all but ignored.

    source:
    http://www.bun.kyoto-u.ac.jp/~suchii/einsteinBM.ht ml [kyoto-u.ac.jp]

  • by drxenos ( 573895 ) on Thursday August 18, 2005 @04:26PM (#13350584)
    Well, one example of where Netwon fails is explaining the rotation of the planet Mercury around the Sun. Since the gravity is so strong that close, Netwon fails, and we must use General Relativity. I believe the planet's orbit (someone correct me) actually spirals.
  • by suitepotato ( 863945 ) on Thursday August 18, 2005 @04:27PM (#13350590)
    If you have it that the values are irrellevant and only the geometery matters, then for E to be conserved and still change c...

    E=(m/(n^2))*((n^2)*(c^2))

    where n is the factor by which the speed of light changes.

    ...which only means that as the speed of light changes, mass must change where it does so that E does not change and violate conservation. And if t is related to c then quite possibly as c approaches infinity m drops towards 0 and the distance between any two points drops towards zero and the speed of time climbs towards infinity and at c=infinity everything happens at once and all distances are zero.

    Conversely if c drops toward zero then mass heads for infinity and when c=0 then mass is infinite, nothing happens, and all distances are infinite.

    It looks like reverse time dilation and one wonders if you can warp space to create a faster local c, can you accellarate normally at such a rate as to counter it and have dilation=0? It doesn't look so much like Star Trek's integral warp speeds as there being a curve on which normal dilation can match warp dilation. Would be interesting to have a high-speed zero dilation trip to the next system and back to check it out with chronometers.

    Just thinking out loud is all...
  • by pin_gween ( 870994 ) on Thursday August 18, 2005 @04:28PM (#13350594)
    What if Einstein's work is an approximation, too. ..

    That's the beauty of science... Science is INQUIRY... it is not static.

    Until someone does prove it was an approximation, we'll use it. Once that occurs, we will use the new figure until someone else is able to make it more accurate.
  • by Robotron23 ( 832528 ) on Thursday August 18, 2005 @04:40PM (#13350702)
    Exactly. Thats one of the problems scientists face with fusion power for example. Fusion as a means of an energy source was proposed back in the fifties. When old Albert was barely in the grave infact. Since then they've made modest progress, as many on /. have no doubt heard, a fusion reactor named ITER was approved for construction in France.

    Thing is, though ITER is widely expected to be relatively (ha-ha) more efficient than past fusion reactors, it'll still be experimental. By that I mean it'll still be inefficient in terms of energy produced from materials used. We have a heck of a long time to go before we can even make an energy "profit" from materials put in. The most optimistic scientists predict 2040 as the crossover point. But then, only time will tell.

    A second problem is that some environmentalists believe all E=MC^2 ever acheived was "The Bomb" and as such try to obstruct progress through protesting etc. It is true that fusion can pollute, but to a much lesser degree than nuclear fission. Still, perhaps in fifty, a hundred, two hundred years time when fusion becomes widely used they'll be chaining themselves to trees and whatnot.

    We'll no doubt find that development in fusion and other methods of power will speed rapidly once oil/natural gas become scarce enough. And with that, hopefully, journeys to Mars, to the Centuari system, and beyond on fusion powered craft.
  • by sane? ( 179855 ) on Thursday August 18, 2005 @04:48PM (#13350774)
    Sure-- it's the formula for "Energy to matter" or something. But why does this matter? How does this relate to Einstein's theories about gravity wells, speed of light, etc.

    First thing to realise is that there are two theories of relativity - special and general. Special came first, is much easier to get your head around, and concerns motion, energy and that equation. The second, general theory came after, concerns gravity and is a complete pig to work with (Riemann curvature tensors [wikipedia.org] anyone?)

    As to why does it matter, the equation shows how you can convert one to the other, how things get screwy as you approach c, and tends to come up and bite you when you follow a perfectly reasonable line of Newtonian reasoning forward and find it ends up complete gibberish. In such circumstances you learn that yes, it does occur in real life, and it helps if you understand it.

  • Heaviside's Equation (Score:3, Interesting)

    by radtea ( 464814 ) on Thursday August 18, 2005 @05:26PM (#13351079)
    http://en.wikipedia.org/wiki/Oliver_Heaviside [wikipedia.org]

    Oliver Heaviside is one of the forgotten men of science, much like Philo T. Farnsworth (inventor of the electronic television) is one of the forgotten men of engineering.

    As well as casting Maxwell's equations in their modern (vector) form, he contributed to work in relativity, and if memory serves first wrote down E=mc^2 in 1892. David Bohm's book on special relativity covers this in considerable detail.

    This is not to diminish the contribution of Einstein, who worked mostly independently of previously known results, but to make it clear that there were others who set the stage for Einstein's great performance.

    The fundamental contribution of Einstein was his ability to show that results that had previously been derived by people like Heaviside and Lorentz with great difficulty from an electro-mechanical dynamical model of the electron could be generalized and proven very simply as a result of a purely kinematic invariance.
  • by wsanders ( 114993 ) on Thursday August 18, 2005 @05:51PM (#13351246) Homepage
    The paper seems to be basically saying that Special Relativity is a special case of General Relativity, which IIRC is true. But then you see the context in the author's homepage, and, well, yes, he does appear to be a little goofy.

    Which all points to the dangers of mixing science with politics and religion. You can piss away a lot of credibility that way, and luckily Einstein never claimed to be an expert at either.
  • Re:E=MC^2 roadblock (Score:1, Interesting)

    by interstellar_donkey ( 200782 ) <pathighgate AT hotmail DOT com> on Thursday August 18, 2005 @06:02PM (#13351324) Homepage Journal
    distance themselves from the poor sap proposing such sacrilege

    No, you're not the only one. When I talk to "scientists" (I'm not one either), and even hint that Einstein's theory might be wrong, it's as if I've shouted out a stream of profanities at church.

    Slowly, but ever so surely, the scientific community is throwing out objectivity and clinging to tradition. In a round about way, scientists are becoming the new priests; just as a man of the cloth devotes years of study to the divine and carries a significantly greater knowledge and understanding of the mystical over the lay person, the scientist too follows a rigorous course of study and understands the physical world in a far more advanced way.

    The objective is the same: "The search for the truth". But the key difference is that scientists are supposed to be objective in that search. I'm disappointed when I ask a particularly religious person a tough question, and she uses the "I know it's true because it's in the bible" response. I'm just as disappointed when I ask a scientist an equally tough question and get an "I know it's true because it was published in the journal of XYZ"

    From an objective perspective, the scientist can typically be more confident in the validity of something published in a journal of note because it is assumed conclusions were reached using the scientific method and stood up to rigorous peer review. But these days, you will never see anything published that contradicts the core beliefs of the scientific community.

    A scientist today who stumbles upon a discovery that, among other things, disproves the theory of relativity, and who can make a compelling case to justify further expenditure of money and resources to bring his hypothesis to fruition, has no chance whatsoever of receiving funding. In fact, if he chose to continue this work and be outspoken about it it's likely he'd lose is position if he worked at a university or think-tank. He would be an outcast and a pariah in the academic world, even though all of his conclusions have been reached through objective reasoning via the scientific method.

    This kind of closed mindedness in the academic world is eerily similar to the world some time ago when the Church prohibited any science or reasoning which suggested the fallibility of the Church's core beliefs. It was wrong then, and it's wrong now.

    I'm not saying Einstein was wrong. As a laymen myself, I couldn't come close to understanding the nuances of his theory so it would virtually impossible for me to comment on its validity. I'm simply saying that it's folly for the scientific community to not even consider alternatives. (And no, I'm not saying that a religious perspective should be considered; religion has no place in science)
  • Re:Plagiarist? (Score:1, Interesting)

    by Anonymous Coward on Thursday August 18, 2005 @06:13PM (#13351387)
    That does not, of course, in any way diminish Poincare's work - and he did a great deal of work besides just that relating to relativity (he is the father of algebraic topology for instance).

    And more importantly, he almost singlehandedly created the field of dynamical systems.
  • by Michael.Forman ( 169981 ) * on Thursday August 18, 2005 @06:15PM (#13351398) Homepage Journal
    Doggone it! Did I get snookered by a wonk? Thanks for the follow up. I'll be sulking in the corner.

    Michael.
  • by Baldrson ( 78598 ) * on Thursday August 18, 2005 @06:50PM (#13351606) Homepage Journal
    Poincare still believed in the ether, and thus an absolute referene frame and an absolute time. It was Einstein who, with his observations about the very nature of time being relative, did away with a ficntional "local time" and an absolute reference frame.

    No if anyone "observed" that time was relative it was Michelson-Morley [virginia.edu]. Einstein postulated this observation as the basis of a formal system which yielded new testable hypotheses.

  • by SETIGuy ( 33768 ) on Thursday August 18, 2005 @07:38PM (#13351902) Homepage
    Bzzrt. Wrong answer. Motion is relative, acceleration is not.

    Bzzrt. Everyone who doesn't quite understand relativity gets this one wrong. Right answer, wrong reason. The acceleration isn't important. The velocity is.

    Think of it this way. Suppose one twin went to a star 100 light years distant at 0.99995c. Assume he has a magic ship that doesn't accelerate. Just boom and it's moving....

    To the twin that stayed behind, he see the ship take 100 years to get to the star and 100 years to get back, (i.e. 200 years round trip).

    Now look at it from the perspective of the twin on the ship. He turns on the engines and suddenly he's moving at 0.99995c. He gets out his handy dandy ruler and measures the distance to his destination. As expected, it's 100*sqrt(1-v^2/c^2) or 1 light year. Also as expected the trip takes 1 year at 0.99995c. When he gets there, he turns the ship around and starts the trip back, which takes another year.

    So when he gets back to earth he sees that during his two year trip, his brother has aged 200 years.

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