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How Einstein Lost His Bearings, and With Them, General Relativity (quantamagazine.org)

Kevin Hartnett, writing for Quanta magazine: Albert Einstein released his general theory of relativity at the end of 1915. He should have finished it two years earlier. When scholars look at his notebooks from the period, they see the completed equations, minus just a detail or two. "That really should have been the final theory," said John Norton, an Einstein expert and a historian of science at the University of Pittsburgh. But Einstein made a critical last-second error that set him on an odyssey of doubt and discovery -- one that nearly cost him his greatest scientific achievement. The consequences of his decision continue to reverberate in math and physics today.

Here's the error. General relativity was meant to supplant Newtonian gravity. This meant it had to explain all the same physical phenomena Newton's equations could, plus other phenomena that Newton's equations couldn't. Yet in mid-1913, Einstein convinced himself, incorrectly, that his new theory couldn't account for scenarios where the force of gravity was weak -- scenarios that Newtonian gravity handled well. "In retrospect, this is just a bizarre mistake," said Norton. To correct this perceived flaw, Einstein thought he had to abandon what had been one of the central features of his emerging theory. Einstein's field equations -- the equations of general relativity -- describe how the shape of space-time evolves in response to the presence of matter and energy. To describe that evolution, you need to impose on space-time a coordinate system -- like lines of latitude and longitude -- that tells you which points are where.
Another interesting read on Quanta: Why Stephen Hawking's Black Hole Puzzle Keeps Puzzling.

21 of 119 comments (clear)

  1. Einstein wouldn't happen today by Anonymous Coward · · Score: 5, Interesting

    In this era of computers and CPU's and constant distraction, he wouldn't have managed to get to even first realization. The Theory of Relativity was a triumph of abstract thought; this is something that doesn't really happen anymore.

    1. Re:Einstein wouldn't happen today by Anonymous Coward · · Score: 3, Interesting

      "Abstract thought" still occurs. It's just that you best keep your mouth shut or wind up being labeled a crackpot.

    2. Re:Einstein wouldn't happen today by Anonymous Coward · · Score: 2, Insightful

      If Einstein didn't come up with it, someone else would have in the next 5 years. He wasn't working in a vacuum. The idea that matter and energy are interchangeable some way was already well on it's way by Poincaré and others before Einstein. Lorentz already described time dilation and the Lorentz transformations is pretty much the basis of special relativity.

      Look at Hawking and the state of the art now in theoretical physics. You have many people that are/were probably on the same level as Einstein was, it's just getting more and more complicated to come up with new shiny groundbreaking theories.

      If anything, research will more faster, because there are more ways to communicate.

    3. Re:Einstein wouldn't happen today by HP+Hovercraft · · Score: 2

      This is why I've been contemplating switching to a feature phone and having only 1 personal computer. Maybe even get rid of a phone altogether. The problem is the rest of the world operates in the internet/smartphone paradigm, so I would be handicapping myself. But the distractions abound and continue to grow. There is no respite. Since we are all addicted to our devices, we are all equal slaves, so it doesn't really improve our lives since we are all "advancing" at the same rate.

    4. Re:Einstein wouldn't happen today by slew · · Score: 2

      If Einstein didn't come up with it, someone else would have in the next 5 years. He wasn't working in a vacuum.

      Actually there is considerable evidence that Hilbert was basically working on general relativity at the same time as Einstein and submitted an article for publication 5 *days* before Einstein's publication (although Hilbert needed to work out a few changes with the publisher in his result and his formulation wasn't published until 3 months later). There is an on-going dispute on who actually got the math right first for the correct field equations, although most agree that the foundational ideas/inspiration about Relativity were from Einstein...

      https://en.wikipedia.org/wiki/...

    5. Re:Einstein wouldn't happen today by GuB-42 · · Score: 2

      In fact I believe that what drive theoretical physics is not the genius of a few scientists but precision and observation.
      A few centuries ago, there is no way we could have observed the effects of relativity, measurements weren't precise enough, and we had too many unknowns. If Newtonian physics give the right answer within the margins of error of the time, then there is no reason for another, more complex theory to exist.
      In order for science to advance, we first need data to disprove the theory of the time with reasonable certainty, and then, we can search for a better model. Usually, the new model comes relatively soon after the observation.

      In fact, that's the problem we have now with the string theory. It explains everything, but we don't have enough data to refine it and test hypothesis.

    6. Re:Einstein wouldn't happen today by DrJimbo · · Score: 2

      I looked at some of the pages on your site trying to find an example of an actual prediction of spring-and-loop theory, not just a bunch of hand waving. For a theory that you claim solves so very many problems while the existing theories are trash, it shouldn't be so hard to come up with one explanation.

      So please, point me to an example of how to use SAL to make a numerical prediction. Since you claim to have a better replace for pretty much all of the existing mainstream physics theories there should be a plethora of worked examples that make numerical predictions. The deflection of light by the sun, the perihelion precession of Mercury, the radius of a hydrogen atom, its energy levels, the fine structure constant. The list is almost endless.

      Your saying that most of the existing theories are trash even though they make amazingly accurate predictions about many aspects of the natural world around us makes it appear you are a crackpot. The apparent lack of any numerical results from your new theory that replaces them seems to seal the deal. I think it would be really really cool if you have come up with a better theory. If you can show me a worked example then I will convince mainstream physicists whom I have worked with that they should stop working on string theory and the standard model and general relativity and instead follow your lead. It would be by far the biggest shake up of physics in history. You will almost certainly win a Nobel Prize.

      But until I see a worked example, you seem to be just another crackpot who is muddying the waters in order to garner undeserved attention.

      --
      We don't see the world as it is, we see it as we are.
      -- Anais Nin
  2. He's not wrong. by Njorthbiatr · · Score: 2

    Gravity exists in the real word, independent of any coordinate system and it behaves consistently. There's no reason why it shouldn't be able to be described as such; we just don't know what that description is.

    Saying that "oh noez Einstein ur on a wild goose chase!" is pretty darn silly.

    1. Re:He's not wrong. by fermion · · Score: 2

      Gravity tends to create it's own reference frame which can then be used to construct a coordinate system that can then be used to model the data analytically. All natural phenomena is independent of human constructed coordinate systems. It is true that classical physics is dependent on the reference frame, at least to some extent, but that is one of the many assumptions made.

      --
      "She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
    2. Re:He's not wrong. by tinkerton · · Score: 4, Interesting

      Classical physics does not depend on a reference frame as long as the limitspeed is infinite and until 1880 or so that was the assumption. I mean it was known that the lightspeed was finite but there was no reason to believe it was the limitspeed. You can turn newtonian mechanics into a covariant system for general coordinate systems but why would you do that? If you want to describe a merry go round , don't get all that overhead and use a shortcut.
      Then with special relativity you could again decide to do the same: support general coordinate systems, make it work for accelerated observers. You could still classify it as special relativity.

      It was Einstein who decided we couldn't avoid to formulate things in a covariant manner, and the example was that inside an elevator it was strictly impossible to distinguish between floating in space or plummetting towards the earth in free fall and and likewise there was no distinction between standing on the surface of the earth and being pulled in space.
      Therefore the math had to be the same too.

  3. Re:FRAUD by Anonymous Coward · · Score: 2, Insightful

    Oh, hi Ken. Thanks for sharing your videos with us. But why post here 3x as AC? Just come out and own it.

  4. Was it a mistake? by tomhath · · Score: 5, Insightful

    the monumental effort to reconcile general relativity with quantum theory flounders in part because of the difficulty of developing a theory of quantum gravity that has the same general covariance Einstein achieved with his field equations. “In some sense you could argue the reason we don’t have an adequate quantum theory of gravity is we don’t know how to express the solutions to Einstein’s equations in a way that completely removes any kind of coordinate dependence,” said Weatherall.

    It sounds like he recognized that there was something he couldn't explain, so he backed off a bit and looked for the explanation rather than charge forward and risk looking foolish.

    1. Re:Was it a mistake? by shoor · · Score: 2

      Einstein apparently consulted some 'pure' mathematicians for help with some of this. From the wikipedia article on David Hilbert:

      By early summer 1915, Hilbert's interest in physics had focused on general relativity, and he invited Einstein to GÃttingen to deliver a week of lectures on the subject.... Einstein learned that Hilbert was also working on the field equations and redoubled his own efforts. During November 1915 Einstein published several papers culminating in "The Field Equations of Gravitation" ...Nearly simultaneously David Hilbert published "The Foundations of Physics", an axiomatic derivation of the field equations ... Hilbert fully credited Einstein as the originator of the theory, and no public priority dispute concerning the field equations ever arose between the two men during their lives....

      Additionally, Hilbert's work anticipated and assisted several advances in the mathematical formulation of quantum mechanics....

      Throughout this immersion in physics, Hilbert worked on putting rigor into the mathematics of physics. While highly dependent on higher mathematics, physicists tended to be "sloppy" with it. To a "pure" mathematician like Hilbert, this was both "ugly" and difficult to understand. As he began to understand physics and how physicists were using mathematics, he developed a coherent mathematical theory for what he found,...
        Hilbert said "Physics is too hard for physicists", implying that the necessary mathematics was generally beyond them; the Courant-Hilbert book made it easier for them.

      --
      In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
  5. Re:"lost his bearings" and "greatest physicist" by tinkerton · · Score: 2

    I didn't know Maxwell ever said that but I know he was pretty damn smart and he knew about the montgolfiere, about catapults and about primitive rockets, so I'm thinking his quotes about flying will have been a bit more subtle than 'it's impossible for heavy things to fly'. There were no lightweight engines at the time that's for sure so technically it was not yet possible.

  6. But got his bearings ... by CaptainDork · · Score: 3, Interesting

    ... back.

    WTF is this?

    Hawking passes and we get Slashdot Esquire magazine?

    --
    It little behooves the best of us to comment on the rest of us.
  7. Re: Questions by Falconhell · · Score: 3, Funny

    Its hard to explain after Harrods was destroyed by the Vogons.

  8. Re:Questions by Anonymous Coward · · Score: 5, Insightful

    What actually happens when matter turns to energy and back?

    It has never been observed to completion, only buildup of mass on high-speed particles and significant energy release on disassembly of atoms.

    What's the difference between energy that is electromagnetic and energy that is motion?

    How it interacts with other energies.

    Why the difference?

    They are essentially different, but also somewhat similar. That's why you are having trouble disconnecting the similarity in names from the difference in meaning.

    Can you turn motion energy into photon energy?

    There are many means of conversion.

    Why not?

    False.

    Where does the value of C come from?

    Observation and calculation.

    Why is there a limit at all?

    We suspect there is a limit because Maxwell's Equations have an asymptote at that value. We accept that there is a limit because high energy testing shows the predicted behavior.

    Why is that limit exceeded by observation?

    It hasn't been.

    How come there are so many forces?

    There are 4.

    Why is gravity only an attraction force and others not?

    Gravity and the strong nuclear force are attraction, the weak nuclear force is repulsion. Magnetism is directionally attraction.

    What is time?

    A direction.

    Why does inertia and momentum require time?

    By definition.

    Why don't things happen instantaneuosly?

    Things do, and trends don't.

    What if they do? How would we perceive that?

    You wouldn't. At best, your perception is functional on the order of 10^42 hypothetical distinct moments per AC observation.

    What would motion look like in a world where everything happens instantaneously?

    Have you been to a rave with a strobe light? Start from there.

  9. Re:FRAUD by Anonymous Coward · · Score: 2, Insightful

    Not only is Ken Wheeler testably false, but the falsify-ability of the electric/magnetic universe theories created the need for relativity.

    If you think there's some physicist conspiracy to keep Einstein in that position, you're stupid wrong. When someone breaks Einstein with a repeatable, testable theory, they will unseat Einstein the same way Einstein unseated Newton.

  10. The evidence suggests not by Roger+W+Moore · · Score: 5, Insightful

    In this era of computers and CPU's and constant distraction, he wouldn't have managed to get to even first realization.

    ....and yet there are thousands of papers published by theorists each year which suggest that people still manage to come up with abstract new ideas in fundamental physics for us to test in our experiments. While it is true that none of these have been as significant as Einstein's papers that's not surprising: if papers this significant came up on a regular basis it would mean that we were doing a really bad job figuring out how the universe works. There were 200 years between Newton and Einstein and another hundred years later we are still only just seeing some of Einstein's predictions for the first time with gravitational waves being the latest discovery.

  11. Re:Risked Missing Out On Fame by tinkerton · · Score: 3, Insightful

    Such a bad example. Darwin delayed much longer than Einstein and it's doubtful whether anyone forced his hand at all.
    He was a brilliant thinker who deserves full credit. Wallace didn't come close in any way.

  12. Re:FRAUD by meglon · · Score: 4, Insightful

    ...and yet every experiment to verify Relativity has shown Einstein to have been correct, whether it was 4 years after, or 100 years after publishing. Your stupid fucking electric universe bullshit requires Relativity to be wrong, yet everything points to Einstein being right.

    Your pseudoscience cult is just fucking stupid.

    --
    Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's