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Is Time Location Dependant?

  1. May 5, 2004 #1
    What are the consequences for Background dependancy in Cosmological Horizon modelling?
  2. jcsd
  3. May 23, 2004 #2
    time is a temporal dimension of spacetime at right angles to the 3 spatial dimensions of spacetime

    if you move through time, you also move through space

    so you can't do one without the other

    time dilation is an illusion caused by one spatial dimension being stretched
    (for the observer) relative to the temporal dimension which remains unstretched
  4. May 23, 2004 #3


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    Staff Emeritus
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    1) In your rest frame you are standing still, and moving through time, but not through space. Of course other intertial observers see it differently. They see you as moving through both time and space.

    2) Time and space dilation through the Lorentz transformations are not illusions for two reasons: first because there is no unversal frame in which the "true" situation could be described, so all we ever have is the relative situation in which the dilations apply, and secondly because the dilations make real physics happen (e.g. the extended lifetime of the cosmic ray muon).
  5. May 23, 2004 #4
    in reality there is no such thing as an unmoving mass in spacetime

    the earth and everything on it is moving at 30000 m/s around the sun

    the sun and all it's planets are moving around a spiral galaxy

    true time (within spacetime) is absolute and unchanging - whilst relative time is variable only between observers in relative motion
    Last edited: May 23, 2004
  6. May 24, 2004 #5


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    In both Einstein's and Galileo's relativity, you are allowed to define yourself as being stationary by centering a reference frame around yourself.
    How or in what frame do you measure "true time" and doesn't this statement (about motion or lack thereof) contradict your first?
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