Is (our) future already exists, according to relativity?

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Hope this is not a redundant Q.
 
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In all classical physics the future is completely and uniquely determined from the past. You have to be careful using phrases like "already exists" to describe the future, but in what sense would you say that the future does not "already exist" if it is completely and uniquely determined from the past? Remember, this is not about relativity, but about classical physics in general.
 
Dmitry67 said:
Yes, it is called a "Block Time", or Eternalism.
http://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time)
But this is ultimately a philosophical matter, a physical theory like relativity can't rule out the possibility that there is some metaphysical truth about simultaneity which has no empirical consequences, although relativity will make such a notion less appealing to anyone who favors razor[/url]
 
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DaleSpam said:
In all classical physics the future is completely and uniquely determined from the past. You have to be careful using phrases like "already exists" to describe the future, but in what sense would you say that the future does not "already exist" if it is completely and uniquely determined from the past? Remember, this is not about relativity, but about classical physics in general.
Relativity just says the laws of physics should be Lorentz-symmetric, it doesn't say they couldn't be stochastic (and I think physicists might still call a stochastic theory "classical" if it didn't have some of the other weird features of QM, like violations of Bell's theorem or the measurement problem).
 
The answer to your question is no, only the "present" exists, that's just plain English. But I think what you mean is "is the future fully determined?" and the answer is, ignoring quantum mechanics, yes.

But this is unsatisfactory. Relativity deals with an unchanging spacetime and you choose an event which you call "myself, here and now" and then relativity will tell you how you will experience things in space and time from that event. But relativity cannot tell you what event you must choose in order to deal with the real (non-hypothetical) world.