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Nature of Space and Time

  1. Aug 17, 2004 #1
    Is the exact nature of space and time known to us yet?
  2. jcsd
  3. Aug 17, 2004 #2
    What is the point of this question?
  4. Aug 17, 2004 #3
    Just to spark a discussion. I would just like to know more about the nature of these two entities.
  5. Aug 17, 2004 #4
    Just offhand, what do you guess is the answer to your question?
  6. Aug 17, 2004 #5
    Haha, I have no idea, that is why I'm asking.
  7. Aug 17, 2004 #6
    OK, I admit that this may sound as a silly question.
  8. Aug 17, 2004 #7
    I think it's a valid question.

    Is it a form of ether?
    Is it a pure vacuum that various forms of energy pass though?
    Is it something else?

    I vote for number three.

    I think space/time is a volume that reflects the various types of energy within.

    If i've been a badboy for making this statement, just send me to TD.
  9. Aug 17, 2004 #8
    "If entropy of ordinary mass (not just black holes) is also proportional to area, then this implies that volume itself is somehow illusory: that mass occupies area, not volume, and so the universe is really a hologram which is isomorphic to the information "inscribed" on its boundaries [Bekenstein]."



    /:set\AI transmedia laboratories

    http://setai-transmedia.com [Broken]
    Last edited by a moderator: May 1, 2017
  10. Aug 17, 2004 #9


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    Dearly Missed

    clearly it is not known

    one way to interpret the question is to say "Do we know how to do geometry at all scales?"

    People are not certain how to do geometry, I think, at very large scales because they do not confidently understand the shape of the universe.
    No simple answer about what space was like a very long time ago---and so on---or how it curves if you go very far out in distance.

    People are also not sure how to do geometry at very small scales.
    It is difficult to see how to probe these very small scales, so as to discover if space is like what we experience at ordinary scale, or something different.

    Perhaps also you could say people lack understanding of nature of space and time because they do not understand why it is bent by concentrations of mass and energy. Why should gravity bend space? One has the equation that says how it is bent, but no proposed mechanism to explain it.

    to me the first obstacle seems to me that we lack understanding of spacetime at very small scales---the rest I would not want to worry about until the boundary of ignorance at microscopic scales is pushed back some more. but that is just a personal view

    getting rid of the singularities of the Big Bang and Black Hole is one step in the direction of dealing with small scale, hopefully
  11. Aug 17, 2004 #10
    No, I do not think the nature of space and time is completely understood. I feel that the theory of special relativity and general relativity are defenately a step in the right direction, but there are so many new theories coming out that have potential for describing the universe (i.e. string theory, holographic theory, etc.), that it is too early for me to decide if we have a definitve answer.
  12. Aug 17, 2004 #11
    The only valid answers to this question are yes and no, and I don't think that anyone will answer with yes.
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