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Our time Vs time

  1. Feb 17, 2007 #1
    There are quite possibly billions of models for time measurement in the known universe using our planetary orbit model.
    Human use of the 24 hour day night sequence and 365 day year using earths orbit of sun and our solar system and our place in our local galaxy and our place in the known universe.has our time model any relationship to time in the known universe.Time measurement is practical to mankind for all the known reasons.
    Is time on earth moving at any speed which is relevent to change in the universe,the big bang model including expansion of the universe.Is time to be calculated in correllation with the speed of the expansion of the known universe,or a seprate model thet seperates time measurement from the model of expansion.
    Or is the earth naturally being part of the universe automatically move in conjunction with the universes expansion and our model of time keeping as such become relevent.
  2. jcsd
  3. Feb 18, 2007 #2


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    Science Advisor
    Gold Member

    Reading material:
    Advanced Topics in Cosmology: A Pedagogical Introduction
    Authors: T. Padmanabhan
    Try to avoid using the word 'seprate'. It diminishes your credibility.
  4. Feb 24, 2007 #3
    Sorry for the spelling mistake,I always wanted to have credibility.
  5. Feb 24, 2007 #4
    Sure, time is determined by number of cycles passed, such as the number of tick and tocks which have occured on a clock, the number of times the earth has gone around the sun, or more accurately, the "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom" which is the definition of the second.

    Earth is moving with respect to the cosmic background radiation originated from the "early universe", so any movement with respect to this expanding radiation field could be thought of as a deviation from the norm. Any increase in such velocity would represent a slow down in the clock.

    Time is calculated without considering the expansion of the universe. However, if you mean the time since (t=0) in the big bang, I will say this - the correlation is very weak since the expansion of the universe varies along the line of sight.

    The earth, sun, and galaxy is moving with respect to the cosmic background radiation, so the "clock rate" will be different than that of the "mean clock rate".
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