This is very interesting, if I can just get my head round it. "Traditional" thermodynamics basically tells us that a closed system in a macroscopically distinct state (and that is able to do so) will evolve with high probability towards a state that is macroscopically indistinguishable from most of the other states it can evolve into. However using quantum phenomena like entanglement and uncertainty could root this apparently emergent statistical phenomenon in some fundamental physics. Since the "emergent" version should work anyway - with virtually *any *laws of physics - we appear to have a surfeit of explanatory power!
However I need to get my head around it some more. On 21 November 2014 07:26, Richard Ruquist <[email protected]> wrote: > "statistical-mechanical ensembles arise naturally from quantum > entanglement" > > > http://people.physics.anu.edu.au/~tas110/Teaching/Lectures/L5/Material/Lloyd06.pdf > > a lecture given by Seth Lloyd > > QUANTUM THERMODYNAMICS > Excuse our ignorance > Classically, the second law of thermodynamics implies that our knowledge > about > a system always decreases. A more flattering interpretation connects > entropy > with entanglement inherent to quantum mechanics. > SETH LLOYD > is in the Department of Mechanical Engineering, > Massachusetts Institute of Technology, 77 Massachusetts > Avenue, Cambridge, Massachusetts 02139-4307, USA > > On Thu, Nov 20, 2014 at 11:30 AM, Bruno Marchal <[email protected]> wrote: > >> >> On 20 Nov 2014, at 02:15, George wrote: >> >> Hi everyone >> >> >> This post is relevant to a few threads in this list >> >> “Reversing time = local reversal of thermodynamic arrows?” and “Two >> apparently different forms of entropy”. >> >> >> I am sorry that I haven’t posted to this list for a while. I have been >> very busy with my work. >> >> In my latest research I have found that Quantum Mechanics, in particular >> the Pauli Exclusion Principle, can be used to go around limitations of >> classical physics and break the Second Law. >> >> >> >> Papers describing the research are publicly available at >> >> >> >> http://www.mdpi.com/1099-4300/15/11/4700 >> >> >> >> and >> >> >> >> >> https://sites.google.com/a/entropicpower.com/entropicpower-com/Thermoelectric_Adiabatic_Effects_Due_to_Non-Maxwellian_Carrier_Distribution.pdf?attredirects=0&d=1 >> (Currently under review) >> >> >> >> Nice to hear from you George. It has been a long time indeed. I will take >> a look, but up to now, my computer refuses to open the document ... >> >> To be frank, I doubt very much that QM could break the Second Law. If you >> could sum up the reason here, it would be nice. Take your time (I am also >> rather busy those days). >> >> >> Best, >> >> Bruno >> >> >> >> >> These papers describe experimentally observed thermoelectric adiabatic >> effects (the existence of a voltage without any heat flow, and the >> existence of a temperature differential without any input current.) >> >> >> >> Here is some background: The story begins with a thermodynamicist of the >> nineteenth century, Josef Loschmidt, who challenged Boltzmann and Maxwell >> regarding the Second Law. Loschmidt argued that the temperature lapse in >> the atmosphere could be used to run a heat engine, thereby violating the >> Second Law. Loschmidt was wrong as shall be explained below but it is >> instructive to go through his reasoning. Loschmidt argued that the >> atmospheric temperature lapse occurs spontaneously, is self renewing and is >> due to the decrease in kinetic energy of molecules as they go up against >> the gravitational gradient between collisions. Therefore the atmospheric >> temperature decreases adiabatically with altitude and could be used to run >> a heat engine. >> >> However, Loschmidt ignored the fact that molecular energies are >> distributed over a range of values and that gravity separates the molecules >> according to their energy in a fashion analogous to a mass spectrometer >> separating particles according to mass. Molecules with greater energy can >> reach greater heights. If one assigns a Maxwellian distribution to the >> molecules (exponentially decaying function of energy), then any vertical >> translation of a group of molecules results in a lowering of their kinetic >> energy, corresponding to a left shift of their distribution. After the >> distribution is renormalized to account for the lower density at higher >> elevation, the original distribution is recovered indicating that the gas >> is isothermal, not adiabatic as Loschmidt conjectured. This effect is due >> to the exponential nature of the distribution. An addition (of potential >> energy) in the exponent corresponds to a multiplication of the amplitude. >> So Loschmidt was wrong: the Loschmidt effect (lowering of KE with >> altitude) is exactly canceled by the energy separation effect caused by >> gravity. However he was only wrong with respect to gases that follow >> Maxwell’s distribution. >> >> >> >> Electrical carriers in semiconductor materials are Fermions following >> Fermi-Dirac statistics and the above argument does not apply to them. When >> subjected to a voltage they do develop a temperature gradient. This >> temperature differential is hard to observe because it is promptly shorted >> by heat phonons. As experiments at Caltech have shown (see my papers), it >> can be observed in certain circumstances such as in high Z thermoelectric >> materials in which electrical carriers and heat phonons are strongly >> decoupled. The Onsager reciprocal of the temperature differential is a >> voltage differential which has also been experimentally observed. >> >> >> >> The two papers above describe these results in detail. >> >> >> >> In summary, quantum mechanics, in particular the Pauli Exclusion >> Principle, can be used to bypass classical mechanics in generating >> macroscopic effects violating the Second Law. >> >> Other relevant papers: >> >> 1) Hanggi and Wehner arXiv:1205.6894 >> <http://arxiv.org/abs/1205.6894> show that any violation to the >> Uncertainty Principle would result in a violation of the Second Law. This >> does not contradict my research which shows use of QM to violate the Second >> Law. The paper also suggests for future research the reverse >> proposition that any violation of the Second Law would result in a >> violation of the Uncertainty Principle. This, if true, would contradict my >> research. >> >> 2) Lloyd, Seth, >> http://people.physics.anu.edu.au/~tas110/Teaching/Lectures/L5/Material/Lloyd06.pdf. >> This paper discusses derivation of 2nd Law from QM. >> >> >> I welcome any comment or criticism that you may have. >> >> >> George Levy >> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/d/optout. >> >> >> http://iridia.ulb.ac.be/~marchal/ >> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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