Recent content by Russell E

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    How Do Contradictory Metrics Align with GR Field Equations?

    There is only one unique spherically symmetrical solution to the vacuum field equations (see Birkhoff's theorem), and it's the one Schwarzschild described. His description differs only in appearance from how the Schwarzschild solution is commonly presented, due to the use of an unusual radial...
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    How Do Contradictory Metrics Align with GR Field Equations?

    Not true. The two actually are equivalent. This is well known. You can find a discussion of this here http://www.mathpages.com/rr/s8-07/8-07.htm starting about half-way through the article, beginning with the words "Interestingly, the solution in Schwarzschild's 1916 paper was not presented...
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    Arthur Eddington: Early GR Experts & His Views

    I don't see anything in Einstein's personality that would encourage a belief that no one (or very few) understood his ideas. In fact, his was quite accommodating when it came to issuing endorsements of other peoples' books and articles on his work. (Witness his endorsement of Fuller's...
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    Arthur Eddington: Early GR Experts & His Views

    Yes, I meant Synge. I'll try to edit my message to fix that. I don't think we're talking about a "myth in Einstein's personality". Obviously in early Nov 1915 it was fair to say that the number of people who understood general relativity was 0, and by the end of November several people had...
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    Arthur Eddington: Early GR Experts & His Views

    The idea of a "list" of people who "understand general relativity" is obviously silly. The New York Times may have encouraged that notion in the general public in 1919 when they reported in their eclipse article that "only 12 men in the world understand Einstein's theory". They apparently...
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    Is Special Relativity a field theory?

    It isn't that SR is "more than electrodynamics", it's that SR is not electrodynamics at all. SR is applicable to electrodynamics, as it is applicable to every other branch of physics, but SR itself is simply the assertion that all physical phenomena are Lorentz invariant. This discussion is...
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    Is Special Relativity a field theory?

    Ah, I see the source of your confusion now. You're conflating special relativity with a specific (and now obsolete) theory of electrodynamics. What we now call special relativity was developed in Part 1 of the 1905 paper (which Einstein called "The Kinematical Part"). In Part 2 of that paper...
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    Is Special Relativity a field theory?

    It doesn't. You're completely mis-reading the sentence. It refers to three things: A. The two postulates of special relativity B. Maxwell's theory for stationary bodies C. A theory of electrodynamics for moving bodies Einstein's quote says that A suffices to attain C based on B. In...
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    Is Special Relativity a field theory?

    I don't disagree with Einstein's remark at all, but I disagree with what you think it means. At the time, physicists knew how to apply Maxwell's equations to stationary systems (for classical phenomena), but there were some recognized ambiguities and uncertainties in how to apply Maxwell's...
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    Is Special Relativity a field theory?

    Right, and Einstein intuited that it was a false choice, and that the answer must actually be a hybrid between the two, as indeed it turned out to be. He already knew in 1905 that Maxwell's equations could not claim unlimited validity, because EM radiation exhibits aspects of an emission model...
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    Is Special Relativity a field theory?

    I think that pre-print is actually a counter-example to your statement. You say "Most experts assert that this theory leads to GR and offers no new insights", and yet the cited pre-print argues just the opposite, i.e., it argues that the "field and geometrical approaches lead to quite different...
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    Does an explicit list of 20 independent compenents of Riemman exist?

    You can find a discussion of the 20 independent components of the Riemann tensor in section 8 of this web page: http://www.mathpages.com/rr/appendix/appendix.htm
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    Curvature of Manifolds: Understanding Relative Concepts

    Yes, but that's not the function you need to minimize. What you've written there is minimizing the integral of the square root of (dr)^2 + (dtheta)^2, as if that represents the incremental distance ds along a path of dr and dtheta. But that's wrong, because we can actually perform measurements...
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    Is the Sun invisible at relativistic speeds? Part II

    There's a valid distinction between "invisible" in the sense of "transparent", versus in the sense of "completely dark". However, in this context it's a moot point, because in the limit as the speed approaches c the apparent size of the Sun goes to zero, so the distinction between transparent...
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    Is the Sun invisible at relativistic speeds? Part II

    The video is correct, and what pervect said is also correct. They are describing two different things. The video is talking about the visual image of a moving object, which consists of light reaching the observer's eye that has traveled different amounts of time to reach the eye (because...
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