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Beyond standard Thermo Laws

  1. Apr 26, 2013 #1

    marcus

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    So one can even have "beyond standard Thermodynamics" :biggrin: I just came across this and it seems interesting.

    http://arxiv.org/abs/1207.0434
    Laws of thermodynamics beyond the von Neumann regime
    Dario Egloff, Oscar C. O. Dahlsten, Renato Renner, Vlatko Vedral
    (Submitted on 2 Jul 2012)
    A recent development in information theory is the generalisation of quantum Shannon information theory to the operationally motivated smooth entropy information theory, which originates in quantum cryptography research. In a series of papers the first steps have been taken towards creating a statistical mechanics based on smooth entropy information theory. This approach turns out to allow us to answer questions one might not have thought were possible in statistical mechanics, such as how much work one can extract in a given realisation, as a function of the failure-probability. This is in contrast to the standard approach which makes statements about average work. Here we formulate the laws of thermodynamics that this new approach gives rise to. We show in particular that the Second Law needs to be tightened. The new laws are motivated by our main quantitative result which states how much work one can extract or must invest in order to affect a given state change with a given probability of success. For systems composed of very large numbers of identical and uncorrelated subsystems, which we call the von Neumann regime, we recover the standard von Neumann entropy statements.
    22 pages, 5 figures.
     
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  3. Apr 29, 2013 #2

    RonL

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    Thank you marcus, for sharing this link.
    It seems to confirm my mechanical intuitions that I have so poorly tried to convey from times past on this forum.
    I will have to put much study into a paper that is far advanced beyond my academic background, but to say what I think is being stated in the paper (forgive my simplicity) a two part system that is maintained in a state of nonequilibrium will be able to gain from a spontaneous thermal transfer of heat in the cold reservoir along with heat brought in with the air.

    The basics of my thought is, an insulated hot reservoir along with heat brought in with an open cycle air system and a refrigeration type closed system that takes advantage of spontaneous flow of heat in, both air and refrigerant will result in an excess of heat that equates into a work output needed in order to prevent the system from reaching a point of equilibrium where heat ceases to transfer.

    I think a large amount of confusion generated in my past statements stems from having all mechanical functions nested inside a single enclosure that is in contact with the environment, the shell of which is cold just at a temperature that will not develop an ice formation, which would become an insulator between the shell and environment ( air or liquid).

    The paper seems to imply this heat/work imbalance, I hope this is not too presumptuous on my part to state my thoughts in this matter:redface: as it has been a focus of mind that goes back far too many years.

    Now a lot of study ahead, just hope I have not completely missed the point.

    Ron
     
    Last edited: Apr 29, 2013
  4. Apr 29, 2013 #3

    marcus

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    People might be interested in video of a seminar talk given today
    http://pirsa.org/13040112/
    by Dahlsten, one of the authors of the paper.
    The abstract is the same as the paper's:

    PIRSA:13040112 ( Flash Presentation , MP3 , PDF ) Which Format?
    Laws of thermodynamics beyond the von Neumann regime
    Speaker(s): Oscar Dahlsten
    Abstract: A recent development in information theory is the generalisation of quantum Shannon information theory to the operationally motivated smooth entropy information theory, which originates in quantum cryptography research. In a series of papers the first steps have been taken towards creating a statistical mechanics based on smooth entropy information theory. This approach turns out to allow us to answer questions one might not have thought were possible in statistical mechanics, such as how much work one can extract in a given realisation, as a function of ...

    Ron, don't be discouraged. Your first ideas may not work out but it's good to get immersed in thermodynamics and think about it. This paper may not confirm your first ideas because it says that conventional results are recovered under the usual circumstances. I can't say much that is helpful except not to be disappointed. The talk looks interesting. I'm going to watch part of it now.
     
  5. May 16, 2013 #4

    RonL

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    marcus, thanks for your words of encouragement:smile:

    For reasons on my part, it was a struggle to study through the 22 pages of the paper, but in the end and on the last page the summary does confirm the possible validity of thoughts that have been impossible for me to convey in an understandable and clear picture.
    The correct conclusion as I see it, is that a combination of design that brings together (for example) a water wheel and heat engine, both working in unison to a collective output can in fact violate the Kelvin statement. (or any number of other mechanical combinations)
    Unlike the waterwheel, a system that makes use of compressed air can be used (almost) anywhere on the face of the earth.

    A number of designs that have been described (by me) have resulted in locked threads, infraction points and likely a close call for being banned.:redface: A lot of study ahead in an attempt to understand proofs as well as terminology in this 22 page document.

    If I have understood correctly, what the presentation is saying, then correlating my thoughts of design with the steps of proof as presented, might just give me the ability to justify many of my comments.
    Yes! the first and second laws stand solid and true, but in my mind they demand the possibility of a process that fills the gap between Carnot and the limit of the second law.

    Thanks again
    Ron
     
  6. May 31, 2013 #5

    RonL

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    Well I'm still working hard at this topic, as time permits.:smile:

    A couple of questions about things studied in an effort to learn and understand what is related to this paper and the stated game of "single shot work extraction".

    The experiment by Madame Chien-Shiung Wu in 1956, the book "From Atoms To Quarks" made mention of the test conditions of Cobalt 60 reduced to a temperature just a few 10th's of a degree above absolute zero, the sample was exposed to a uniform magnetic field that brought the atomic nuclei to a uniform alignment and that the condition could be held for a time of only 15 minutes.
    Was the problem of sustaining the test a lack of holding the temperature, or the energy within the sample generating heat at an ever increasing quantity ?

    The point of that question, being....is Brownian Motion a product of chaotic oscillations of the atomic nuclei within the nucleus of any atom ?

    In these pages, mention of "Maxwell's Demon" and the "Szilard Engine" (new to me) led me to a study of the "Brownian Ratchet" and Feynman analyses about why it would produce no useful work. My mind generates changes in mechanical design that overcomes the majority of failure points, which puts me in the forbidden zone of PF, so I'll leave it at that for now.

    The game mentioned in the paper, seems to me, to have several options of strategy which bring about the same results.
    They make the statement... "In particular the second law requires a significant tightening".... would anyone care to expand on how that fits into the current accepted definition ?:shy:

    Hope the questions are not too basic, at my level of study, simple and brief answers should be sufficient.

    Thanks
    Ron
     
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