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Time travel

  1. Dec 10, 2003 #1
    Time travel is empirically impossible for the simple reason that there is no empirical past. The past exists only as memory and history. The atoms (molecules and subatomic particles) that composed the past have simply rearranged themselves and comprise the present.

    Travel to the past would require the atomic arrangements of the present be returned to the past configuration of the past to recreate the past. Even this would not be traveling to the past because this duplication of the past would still constitute the present. Likewise, the future does not exist until the atoms of the present rearrange themselves to become the future, but this only happens in present. Empirically, one is always locked into the present.

    Fortunately, time travel is possible in the imagination and in science fiction movies where it is often very entertaining.
  2. jcsd
  3. Dec 11, 2003 #2
    Empirically speaking..... as Emmanuel Kant once postulated that the character of this experience could be a product of the structure of our minds rather than the structure of "reality". Also, I realize that Einstein also remarked that from the perspective of relativity, this perception of experience is nothing more than an illusion.
  4. Dec 13, 2003 #3
    If the structure of reality is NOT manifest in the structure of our minds, is it manifest in the structure of reality?
    If so, the knowledge of such structure would be manifest in the structure of our minds.
    It would be a long futile road if we chose to define reality as something other than what we define it as.
    As long as time is the measure of physical systems, those same systems will be arranged in a manner we know as the present.
    When and if they are ever arranged in a manner we now remember as the past, we too will be part of that arrangement and we will call it the present.
  5. Dec 23, 2003 #4
    That's easy to say (although I wouldn't use the word "past" four times in a sentence if I said it), but we don't *really* understand the nature of time. Defining it as "the interval between two events" is self-referential, because it implies "the [time] interval...". There are physical intervals between events as well. ALL our definitions of time use "time" as a defining word, whether implied or stated.

    What if time was a wave or progression of a frequency? And you could shift that frequency in a local space and move time forward or backward?

    What if time was a pool, constantly filling, with each new layer of water molecules being the state of our universe at a given moment? What if you could "stop floating", and let the water rise around you? You would travel through time.

    I'm not saying I believe in time travel, but there's always possibilities. Never say never.
  6. Feb 15, 2004 #5
    Time travel is possible and it's implementation would undoubtedly have something to do with
    bending locally timespace in the way so it would match the curvature of the time space
    in the “moment” to which we want to travel. Gravitation responsible
    for slowing down the expansion of the universe and directed towards Big Bang (the center of 4D universe) would shift the distortion to the “right time” that one can associate with the “radius of sphere” of our universe (in 3D model) where local curvature matches the one of the universe in the past (shorter radius) or future (longer radius).
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