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Block Time interpretation

  1. Aug 21, 2004 #1
    Hi, I posted this question in Astronomy & Cosmology but by advice of some users I post it here as it has some philosophycal side too:

    It seems to me that block time is an unavoidable consequence of Relativity. The fact that events that still lie in our future must have already been observed by other (hypotetical) observers seems to leave no room for escaping the fact that (at least some of) the events in our future "have already happened".

    To me (a layman) that seems to leave just 2 possibilities: either the future is already totally determined or we live in Everett's-Deutsch many-worlds multiverse.

    Or are there any other alternative interpretations? I know about quantum undeterminacy, but I still don't really get how does it get along with the seemingly unavoidable reality of block time derived from Relativity theory.
  2. jcsd
  3. Aug 21, 2004 #2


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    Gerinski, I find your use of "Already" with future events an unsatisfactory representation of the block time idea. "Predetermined" would be better, because we can't define a timelike path (in special relativity) that visits those future events and time-orders them before our present, which is what "already" sems to mean.

    Block time takes 4-d Minkowski spacetime seriously. Others would say it reifies a useful mathematical idea. Weinberg notably takes the position that spacetime is just a useful metaphor.

    Spacetime diagrams which are used as "intuition pumps" for learners, do not play much part in the thinking of professional physicist. They work instead with the mathematics of the Lorentz transforms. These latter do mix time nad space, but on a case-by-case basis which may suggest the overall idea of spacetime but does not entail it.
  4. Aug 21, 2004 #3
    Thanks SelfAdjoint. I guess I get some of your point, but I admit it's just too bad I'm not trained in physics but just a humble afficionado, I wish I could look at the question from a more educated viewpoint! Just let me remake a bit the question as I did in a parallel thread in Cosmology, but please forgive me if I use an inappropiate layman language, I just hope you get my meaning.
    And of course I don't mean to be right, I just express what my understanding is, expecting to get corrected wherever I'm wrong:

    The fact that 2 events A and B may be perceived by one observer as A happening before B and for another observer as B happening before A is a scientifically accepted relativistic effect.
    It seems therefore scientifically sound that events that still lie in our future may have "already" objectively happened (witnessed by other hypotetical observers), as we are not supposed to have any privileged status versus such other hypotetical observers. Past present and future are subjective labels (or time stamps) attached to objective events, and the sequence of the time stamps is not necessarily unique.

    Until here it seems to me this is hard science and not yet into philosophy.
    Quantum underterminism is also mainstream science.

    I see Multiverse as a scientific theory finding a way out from the apparently contradictory solutions arising from our 2 most respected scientific theories to the scientifically legitimate question wether the future is determined or not.

    My question is if there are any other scientific way outs to this contradiction.
    Thanks again!
    Last edited by a moderator: Aug 21, 2004
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