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Theoretical Entropy Clock

  1. Jan 13, 2013 #1
    Hello dbmorpher here,
    I was looking at some articles on entropy and wondered, could this be used to calculate time?
    Entropy is known as the arrow of time, figurative I know but could actually be used to measure.
    If there was a device that calculated the entropy in a set system couldn't it automatically calculate it and give a numerical value?
    This would need a set system for all clocks but would render any other non- atomic clocks obsolete because it is based on measurements and calculations instead of gears and circuitry.

    I would like to know if what I said in that last sentence could happen and if I could make one myself.

    I found this
    But I do not understand it very well.
  2. jcsd
  3. Jan 13, 2013 #2


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    Staff Emeritus
    Science Advisor
    Education Advisor

    This is VERY puzzling. What system do you wish to measure the entropy of that is SO reliable as to be used as a clock? And how would this be more accurate than current atomic/Cs clock?

    BTW, the naive link between entropy and the arrow of time is a QUALITATIVE relationship, not a QUANTITATIVE one. Nothing here says that entropy can provide an accurate MEASURE of time.

  4. Jan 13, 2013 #3


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    Staff: Mentor

    Right. I could use a pot of water on my stove as a clock, but it would be cumbersome and not all that accurate.
  5. Jan 15, 2013 #4
    Well from what I have learned entropy is measured not observed, therefore a small calculator sized computer could be fitted to a clock and measure the entropy in the system, the only way for the clock to be inaccurate is if the laws of thermodynamics broke.
    Refute me if I am wrong.
  6. Jan 15, 2013 #5
    Can you not think of all clocks in this way? A wound clock has less microstates available to it than an unwound clock. A clock is that which measures entropy change reliably. Reliably being defined as: it progresses in some constant ratio to other clocks.
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