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Maxwell's Demon

  1. Feb 20, 2005 #1


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    Maxwell's Demon by Hans Christian and Von Baeyer, for those who've read it, is it worth reading?
  2. jcsd
  3. Feb 21, 2005 #2
    Maybe I'm wrong, but why to read a whole book for the Maxwell's demon?
  4. Feb 21, 2005 #3
    I haven't read this book but I have read his book 'Information: The New Language of Science'. I felt that this was definitely worth reading, but at the start he seemed to be trying to show how difficult the subject was. Possibly his other book is similar, so I would say that even if the first chapter seems a bit daunting then you should stick with it.

    1)Hans Christian Von Baeyer is all one name

    2)When I first looked at your post with what seemed like 2 authors, it thought it referred to Maxwell's demon 2 : entropy, classical and quantum information, computing / edited by Harvey S. Leff and Andrew F. Rex., but that's a different book altogether - its a collection of papers about Maxwell's demon, and I would only advise it for those who are keen on finding out about the history of the subject.
  5. Feb 21, 2005 #4


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    oops my mistake, its just that von baeyer was under hans christian.
  6. Feb 22, 2005 #5
    I'd suggest several even (well, at least one). It's a very, very informative experiment to get a grip on entropy, if that's at all possible. Took quite some time for someone to really refute the original logic, too (Szilard).

    http://users.ntsource.com/~neilsen/papers/demon/dpaper.html [Broken]
    Last edited by a moderator: May 1, 2017
  7. Feb 23, 2005 #6
    I don't have anything against the subject, honestly it is among the most interesting ones. I have read about the Maxwell's daemon in a chapter of an entertaining book from G.Gamov, and I think a few pages would be enough. Maybe the interested reader would like to know more.
    Last edited by a moderator: May 1, 2017
  8. Feb 23, 2005 #7
    Let me guess: The New World of Mr. Tompkins ...

    nice, but hardly thorough or extensive. :wink:
  9. Feb 23, 2005 #8
    Yes, you got it! :smile:
  10. Feb 24, 2005 #9
    Thought so.

    Thing is though, that entropy is not only something related to energy, but to information as well. There are subtle differences, some pretty hard to grasp. Therefore I'd suggest to anyone really reading up on MD, because it is one of the rare instances where the two types (energy and information) meet.

    And entropy plays an enormous - albeit somewhat hidden - role in just about everything we do. It keeps us sane, for one - through forgetting. Even if we don't really forget, but no longer focus on something - essentially because we do no longer wish to put in so much effort (energy) into something bad or that's gone wrong in the past.

    Something much overlooked in A.I. circles, too. :wink:
  11. Feb 24, 2005 #10
    Entropy v Forgetting :surprised
    What is the relationship?
  12. Feb 24, 2005 #11
    Well suppose you turn off your computer. The information in it is lost (forgotten) due to dispersion of the energy of the system to the environment - the increase of entropy.

    So I've told you how entropy is really the same as forgetting. Well, now you should forget it, because I'm going to tell you the exact opposite :confused:

    When Maxwell's demon finds out the position of a particle he has gained some information. To reset the system to its original state he has to get rid of this information. But since physics is reversible he has no mechanism for doing this. If he could then we could build Maxwell's demon type devices. Thus the second law of thermodynamics rests on the fact that no information is ever truly forgotten.
  13. Feb 24, 2005 #12
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