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Maxwell's Demon Possibility?(Entropy)

  1. Dec 13, 2003 #1
    "Maxwell's Demon" Possibility???(Entropy)

    About a hundred years ago, James Clerk Maxwell imagined 2 adjacent chambers, each containing gas and both sealed to the outside world. The chambers are also sealed from one another, except for a single gate the size of a gas molecule. Guarding this gate would be an intelligence with one power: the ability to discriminate between fast and slow molecules. It would pass slow molecules in one direction only, fast molecules in the other direction only. The net result would, after a time, be one chamber that contained only slow-moving molecules, next to a chamber that contained only fast-moving molecules. In other words, the chambers would not be the same temperature: One hot and one cold. Should such a "Maxwell Demon" prove possible, its discriminatory intelligence would reverse the apparently irreversible entropy, which inevitably has everything existing at the same low temperature? Any Comments?
  2. jcsd
  3. Dec 14, 2003 #2
    Have you ever heard of the ranque-Hilsch vortex tube that separates hot and cold air? It operates simply by virtue of the air flow through the geometry of the device.

    Click here for the thermodynamic aspects of the device.

    Last edited: Dec 14, 2003
  4. Dec 15, 2003 #3
    I have thought about such things, and though the concensus is no, I have a half-baked idea oddly enough also involving a vortex that seems like it would decrease entropy. As it is half-baked I don't care to share it, but if you visit here often I will PM you with the idea, if it proves interesting.
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