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Is the B-theory of Time Presupposed by Relativity?

  1. Jul 17, 2014 #1
    Is it possible to assume relativity is still basically correct and reject the b-theory of time? Or does a coherent description of relativity necessarily presuppose it?

    I find b-theory so repugnant.

  2. jcsd
  3. Jul 17, 2014 #2


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    Looking up "B-theory" in wikipedia, it appears to be a philosophical position regarding time. Obviously I haven't studied this issue much if I had to look up what "B-theory" was :(.

    While I can't answer your question, I can say is that cause and effect in special relativity is modeled through the mechanism of light-cones. Any individual event in space-time has a past (the past light cone), a future(the future light cone), and a 4-dimensonal set of events which are neither past, nor future, usually called "space-like separated events".

    Any pair of space-like separated events (in which neither event is inside the lightcone of the other) will be seen as simultaneous for some observer. Different observers will disagree on their notions of simultaneity (as per relativity of simultaneity).

    While individual events have a past and a future, there isn't any global notion of "past", "future", or "present" imposed by the theory.

    I would suspect if the issue is still being argued over that there isn't any actual resolution of the philosophical issues. Most likely neither theory makes testable predictions, which is what we look for in science and distinguishes science from philosophy. With no testable predictions, there's no way to say that A or B is "wrong", so I would expect that you should be able to do relativity in either A or B philosophy. But perhaps not with equal ease.

    Sorry I couldn't answer your question, I hope my more general remarks were still of interest.
  4. Jul 17, 2014 #3

    Vanadium 50

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    Sorry, but we don't discuss philosophy here.
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