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Another 2nd law Violation Thread

  1. Jul 28, 2010 #1
    I recently attended this lecture by Physicist Daniel Sheehan, any opinions about the 2nd law soon violated in Laboratory Experiments? (and we are not talking about background fluctuations, etc).

    Experimental Challenges to the
    Second Law of Thermodynamics
    D.P. Sheehan, University of San Diego

    Over the last 15 years the absolute status of the second law of
    thermodynamics has come under increased scrutiny. More than two dozen
    distinct challenges have appeared in the refereed scientific
    literature—more than the sum total over the previous 150 years—raising
    the possibility that the second law might soon be shown violable in
    laboratory experiments.

    This talk will survey recently proposed challenges from a number of
    research groups around the world, focusing on those most amenable to
    laboratory test. Possible ramifications of second law violation will also be
    discussed, the most significant of which might be the recyclability of
    environmental heat into usable work. The thermal energy content of the
    atmosphere, ocean, and upper crust is estimated to be more than 10,000
    times that of the world's fossil fuel reserves, making it a potentially
    inexhaustible reservoir of green energy.

    1) “Challenges to the Second Law of Thermodynamics: Theory and
    Experiment” V. Capek and D.P. Sheehan; Fundamental Theories of
    Physics, Vol. 146 (Springer, Dordrecht, The Netherlands) 2005.

    2) “Quantum Limits to the Second Law” D.P. Sheehan, Editor; AIP
    Conference Proceedings, Vol. 643 (AIP, Melville, NY) 2002.

    His work seems extensive, anyone aware of it? All opinions appreciated, Thanks, John
  2. jcsd
  3. Jul 28, 2010 #2
    I don't see why that abstract mentions the total heat content of our surroundings: this thermal energy is constantly replenished. Even if we could freely violate the 2nd law and harness this energy for work (thereby cooling our surroundings), the work (or the friction involved) would simply reheat our surroundings. Since it's a perpetual cycle, it doesn't matter how big the store is.

    Sounds dubiously extraordinary. Does he actually propose a specific violation? (Simply counting dozens of paradoxes is only meaningful if they haven't each been individually resolved..)
  4. Jul 29, 2010 #3
    I like to think of thermodynamics from an extremely classical and practical viewpoint as I am a Mechanical Engineer and my interest is in heat engines.

    In that regard, I'm 100% convinced that the 2nd law holds 100% of the time. However, when you get into quantum it becomes a huge mudfest. For me entropy is Q/T.
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