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I Block Universe vs Presentism

  1. Apr 22, 2016 #1
    Is there a scientific difference, if not, why bother with the block universe model given it is unintuitive?
     
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  3. Apr 22, 2016 #2

    Ibix

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    There is no scientific difference.

    Intuitivity is in the eye of the beholder and extremely context dependent. The block universe is, for many people, very useful for describing things in a frame-independent way, and as a visualisation tool for combining different frames' viewpoints. That is (one reason) why it is taught.
     
  4. Apr 22, 2016 #3
    But it is un-intuitive in the sense that as far as I know no one ever existed that had the intuition that reality would be like that until the concept of special relativity and the belief that presentism was incompatible. Given such circumstances one can see how it was constructed out of necessity, but given that the premise on which it was constructed (presentism was incompatible with special relativity) was wrong, why keep the construction that I thought history kind of showed wasn't intuitive by virtue of it not being any human beings' intuition until the mistaken need for construction arose?
     
  5. Apr 22, 2016 #4

    PeterDonis

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    Why do you think presentism is compatible with SR? (You should probably also clarify exactly what you mean by "presentism".)
     
  6. Apr 22, 2016 #5
    If you read the thread I didn't say I thought it was. I didn't know there was a diverse opinion on presentism. I haven't read the full article but from the first line, it seems like what I meant by presentism https://en.wikipedia.org/wiki/Philosophical_presentism .
     
  7. Apr 22, 2016 #6
    Sorry a poor article I thought. What I meant is, that what exists is that which exists in the present for you.
     
  8. Apr 22, 2016 #7

    PeterDonis

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    You said: "given that the premise...(presentism is incompatible with special relativity) is wrong...". That implies that you think presentism is compatible with SR, or at least that that the proposition that it is is worth considering.
     
  9. Apr 22, 2016 #8
    That you are an entity which is moving through time, and at any point in time there is a past and a future and a present for you
    I asked in the first question, was there any scientific difference between presentism and special relativity. You replied that there wasn't. The answer I then gave was in response to yours.
     
  10. Apr 22, 2016 #9

    PeterDonis

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    I didn't make that reply; someone else did. Your post #3, from which I quoted, was in response to that other person, not me. Please respond to the question that I asked you.
     
  11. Apr 22, 2016 #10

    PeterDonis

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    This is too vague, because "moving through time", "past", "future", and "present" are not defined. I can construct definitions for all of those terms that are compatible with SR, but under those definitions I think most people would say that presentism--the claim that whatever is "present" for you exists for you--is false.
     
  12. Apr 22, 2016 #11

    PAllen

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    How would it be false, as opposed to others having a different philosophy? How could anyone show the proposition "what is present form me exists for me" is false? Perhaps the disconnect is that I am interpreting present and exist locally. I can see issues if present is stated to be a global construct.
     
  13. Apr 22, 2016 #12

    PeterDonis

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    I meant "false" in the sense of "I think most people would not want to adopt it as a philosophy". I agree that there is no way to scientifically test the proposition.

    As I understand it, most proponents of presentism define "present" as something like "my current 3-hypersurface of simultaneity", which is a global construct. I don't know of any version of "presentism" that defines "present" as just "the event on my worldline that I call 'now'". (I have seen the term "solipsism" applied to the latter version, but not "presentism".) But of course this is all terminology anyway, not physics. What I really want to get clear is what name123 means by "presentism", since he's the one that raised the question in the first place.
     
  14. Apr 22, 2016 #13

    Dale

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    With a properly constructed presentism there is no scientific difference. Some people prefer simplicity over intuitiveness.

    PeterDonis' point is essentially that it is actually pretty complicated to make a presentism that works within the confines of relativity. Many people prefer not to bother with all of the complications since they are scientifically unnecessary.

    @name123 Before we can continue any discussion, we need a professional reference for your meaning of presentism. Guidelines on appropriate journals are given in the forum rules.

    Edit: PM me with the reference and I can reopen the thread.
     
    Last edited: Apr 24, 2016
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