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Eggs, Omelets, and Entropy

  1. Oct 29, 2004 #1
    Here's a quote I've read today regarding entropy:

    "You can turn an egg into an omelet, but you can't turn an omelet into an egg."

    1. Is the probability for an omelet to turn back into an egg in a closed system exactly zero? If so, why?

    I know that the Second Law of Thermodynamics states that "entropy in a closed system can never decrease." Based on this, the omelet has exactly 0% chance to turn back into an egg in a closed system. But, given the probabilities associated with QM, there would seem to be some nonzero chance (albeit unimaginably small) that the molecules of the omelet would recombine to reform the egg.

    2. Does the probability for an omelet to turn back into an egg improve if energy is provided to the system?

    Since energy is added to the system, the entropy is permitted to decrease, and therefore there would be a better nonzero chance for the omelet to turn back into the egg. This seems to be related to arguments I've seen regarding the evolution of complexity of life on Earth: given the Sun's constant energy input, entropy on the Earth is permitted to decrease.

    These are my initial thoughts at least; I need some clarification. :smile:

    (The article's context, which is actually cosmology, can be found here: http://www.msnbc.msn.com/id/6348252/. There's an idea floating around that suggests that the total entropy of the universe is infinite...)
  2. jcsd
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