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Entropy and possibilty of reversal thereof

  1. Jun 12, 2008 #1
    Hello Guys

    As Electricity power supply Mechanical Engineer Entropy is a reality we battle with every moment.

    Is the universe an open heat sink or is it closed and entropy will stop at some point in time?

    Due to entropy we die, it would be nice if it could be reversed. In a black hole is there a reversal of entropy of some sort?

    Nevertheless, as I see it entropy will always win in the end.

    The Big Bang singularity must have been a reversal of entropy from total back to zero.

    Who re-wound the entropy clock, so to speak, back?


  2. jcsd
  3. Jun 12, 2008 #2


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    Entropy is a measure of "structure"- which we can think of as "clumping" of energy. When energy has spread out as much as possible, entropy will no longer increase. That is referred to as the "heat death" of the universe.

    There is no evidence of that.

    What evidence do you have that entropy was NOT 0 before the big bang?

  4. Jun 12, 2008 #3
    Not too long ago there was a great deal of debate as to whether Black Hole's actually lowered entropy but I believe a year or two ago Stephen Hawkings showed that black holes actually don't lower entropy because they do not last forever and when they die they return the entropy (possibly plus more).

    But i'm not an astrophysicist
  5. Jun 12, 2008 #4
    Entropy does decrease for short periods of time in some small systems.
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