Recent content by Berislav

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    News Bush's Support of Torture: Global Impact and Un-American Reputation

    Odd. I never thought Bush was into SM.
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    Exotic particles destroying the universe

    No, they would evaporate very quickly. They were likely talking about strangelets.
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    What Are the Best Geek Entertainment Sites?

    Let's attack the UN! o:)
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    What Are the Best Geek Entertainment Sites?

    Yey! http://www.nationstates.net/cgi-bin/index.cgi/target=display_nation/nation=tensor_analysis
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    My kind of death - Funeral at Age 28

    Right in end sound like a good time to end it all. :smile: A guy I know almost drowned. He says that the pain is worse than the one you experience during a hearth attack.
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    My kind of death - Funeral at Age 28

    I'd like to die in bed, but not in my sleep. :biggrin: I don't care what happens to my body afterwards, really.
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    g_{00}=c^2 \left( 1-\frac{2GM}{c^2 r} \right) As you can see the metric blows up in that limit. This is because time has no geometric structure, or meaning as such, in Newtonian physics. No, it blows up. No, it doesn't. That's called gauge fixing. Which doesn't have anything to do with...
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    Yes, my mistake. The appearance of the metric tricked me. I should have checked the curvature 2-form before I said anything.
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    Are you sure that the Riemann tensor of this metric is zero? In my previous post I used: ds^2=-dt^2+R^2(t) (\frac{dr^2}{1-kr^2}+r^2d\Omega^2) There still is a coefficient multiplying dr^2. I think one should say that it isn't physical as R (or a, in your notation) will become negative...
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    I'll attempt to fill in for pervect in the mean time. :smile: The Robertson-Walker metric is derived by assuming homogenity and isotropy (nothing else about the content of the universe): ds^2=-dt^2+R^2(t) (\frac{dr^2}{1-kr^2}+r^2d\Omega^2), where k can be anything, but we can redefine...
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    I didn't mention that spacetime because I never heard about it. :redface: I apologize. :frown:
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    Please check the metric again. You will see that that is not what happens to it. And I think that Wald didn't take that limit because he dealt with SR and Newtonian approximations in one of the previous chapters, so he assumed that the reader understands that that is how one reduces to Newtonian...
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    Advanced books/papers on derivation of Newtonian mechanics from GR

    I am not sure, but I think that if spacetime is approximately flat then gravity is negligable. Also, there is a problem with the fact that Newton's physics has no underlaying geometric structure (i.e, it is not a flat spacetime). If you mean if the spacetime is asymptotically flat then most...
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    Is Black Hole Complementarity Just a Terminology Issue?

    Yes. Because of the principle of equivalence.
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    Antisymmetric 4-Tensor: Hodge/Duality Transformation Explained

    Here's a wikipedia article about it: http://en.wikipedia.org/wiki/Hodge_star_operator I heard that the first reference is often called the 'Bible of GR'.
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