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General relativity vs special relativity

  1. Jan 11, 2015 #1
    Hello, Everybody!

    I'm new to the board, and am happy to have found you!

    I have six questions I can't seem to find the answers to, either in books or online -- yet I know the answers are out there! I'll post each question in a separate thread, and hope that someone who knows far more than I do will be generous enough to assist!

    My first question concerns general relativity vs. special relativity. The question is: Does the spacetime warp created by velocity ultimately hark back to general relativity? In other words, is the gravity created by acceleration and velocity actually creating general relativity?

    Thank you in advance for your help!
  2. jcsd
  3. Jan 11, 2015 #2


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    Gold Member

    That's simply wrong. No space-time warp is caused by acceleration or velocity!
  4. Jan 11, 2015 #3


    Staff: Mentor

    Whether or not spacetime is flat is a frame invariant thing. Relative velocity does not alter the curvature of spacetime.
  5. Jan 11, 2015 #4
    Hi, as already mentioned, your questions contain several errors. But it's still possible to guess what you likely meant:

    According to special relativity, a change in speed results in a change in length contraction as well as in a change in time dilation.
    The basic idea of general relativity was that the effects of constant acceleration - a change in speed - cannot be distinguished from the effects of gravitation. In that way, predictions of special relativity were helpful in the development of a theory of gravitation.

    Einstein explained it for example here (in particular from chapter 20): http://www.bartleby.com/173/
  6. Jan 11, 2015 #5


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    Staff Emeritus
    Science Advisor

    I'm not sure how to interpret this. "The spacetime warp" could maybe be the Riemann tensor, but then "created by velocity" doesn't make any sense in this context. I have a feeling that we are assigning different meanings to words. This makes communication difficult. If I were to reply with some textbook responses about what GR is, I suspect we'd have the same difficulty in the opposite directions.

    Cold you ask something concrete? For instance, would comparing the gravitational effects caused by the low-speed fly-by of a massive body in Newtonian theory to the results that GR predicts for a high-speed ultra-relativistic flyby be helpful to you in answering your question? There is a paper on that I could refer you to, if the answer would be helpful.
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