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BEYOND MAXWELL'S DEMON
http://www.physorg.com/news/2010-11-...on-energy.html
"Maxwell's demon was the invention of Scottish mathematician and theoretical physicist James Clerk Maxwell, who wanted to contradict the second law of thermodynamics (although the name was given to the imaginary being later). This law implies it is not possible to invent a perfect heat engine able to extract heat from a hot reservoir and use all the heat to perform work, because some of the heat must be lost to a cold reservoir. (...) Until now, demonstrating the conversion of information to energy has been elusive, but University of Tokyo physicist Masaki Sano and colleagues have succeeded in demonstrating it in a nano-scale experiment. In a paper published in Nature Physics they describe how they coaxed a Brownian particle to travel upwards on a "spiral-staircase-like" potential energy created by an electric field solely on the basis of information on its location. The team observed the particle using a high-speed camera. The particle had some thermal energy and moved in random directions. When it was moving up the staircase they allowed it to move freely, but when it moved down the staircase they blocked its movement via a virtual wall created by an electric field. The virtual wall therefore acted like a Maxwell’s demon, only allowing the particle to move in one direction, but not forcing or pushing it." If a constant-charge parallel-plate capacitor is immersed in water, a pressure develops between the plates that greatly exceeds the pressure outside the capacitor plates. (W. Panofsky, M. Phillips, Classical Electricity and Magnetism, Addison-Wesley, Reading, Massachusetts, 1962, pp. 112-116). If the capacitor plate is very thin, we can imagine a sharp drop in pressure across it; then the following conclusion is unavoidable: Punching a small hole in the plate will result in an eternal water flow through the hole, from inside to the outside of the capacitor, in violation of the second law of thermodynamics. A few years ago, at the 2002 First International Conference on Quantum Limits to the Second Law, I called the effect "dynamic equilibrium": http://link.aip.org/link/?APCPCS/643/430/1 "Two testable paradigms - the system performing two types of reversible work and the system in dynamical equilibrium - suggest that perpetuum mobile of the second kind in the presence of an operator is possible." The scientific community remained silent and hostile but still from time to time Panofsky-Phillips pressure leaves scientists speechless: http://www.physorg.com/news110191847.html "When exposed to a high-voltage electric field, water in two beakers climbs out of the beakers and crosses empty space to meet, forming the water bridge. The liquid bridge, hovering in space, appears to the human eye to defy gravity." In his 1824 memoire Carnot dealt with two reversible heat engines which DID NOT INTERACT. In 1850 Clausius used NON-INTERACTING heat engines again: http://web.lemoyne.edu/~giunta/Clausius.html "Ueber die bewegende Kraft der Warme" 1850 Rudolf Clausius: "Carnot assumed, as has already been mentioned, that the equivalent of the work done by heat is found in the mere transfer of heat from a hotter to a colder body, while the quantity of heat remains undiminished. The latter part of this assumption--namely, that the quantity of heat remains undiminished--contradicts our former principle, and must therefore be rejected... (...) It is this maximum of work which must be compared with the heat transferred. When this is done it appears that there is in fact ground for asserting, with Carnot, that it depends only on the quantity of the heat transferred and on the temperatures t and tau of the two bodies A and B, but not on the nature of the substance by means of which the work is done. (...) If we now suppose that there are two substances of which the one can produce more work than the other by the transfer of a given amount of heat, or, what comes to the same thing, needs to transfer less heat from A to B to produce a given quantity of work, we may use these two substances alternately by producing work with one of them in the above process. At the end of the operations both bodies are in their original condition; further, the work produced will have exactly counterbalanced the work done, and therefore, by our former principle, the quantity of heat can have neither increased nor diminished. The only change will occur in the distribution of the heat, since more heat will be transferred from B to A than from A to B, and so on the whole heat will be transferred from B to A. By repeating these two processes alternately it would be possible, without any expenditure of force or any other change, to transfer as much heat as we please from a cold to a hot body, and this is not in accord with the other relations of heat, since it always shows a tendency to equalize temperature differences and therefore to pass from hotter to colder bodies." NON-INTERACTION means that the work-producing force generated by the first engine, F1, is independent of the displacement, X2, in the second engine, and vice versa: dF1/dX2 = dF2/dX1 = 0 where "d" is the partial derivative symbol. It can be shown that, if the two reversible heat engines DO INTERACT and the conditions are isothermal, the equation: dF1/dX2 = dF2/dX1 is a consequence of the second law of thermodynamics (Kelvin's version). That is, if the partial derivatives dF1/dX2 and dF2/dX1 are not equal, heat from a single reservoir CAN, cyclically, be converted into work, in violation to the second law of thermodynamics. This is the first testable paradigm - "the system performing two types of reversible work" - referred to above (the second one is "the system in dynamic equilibrium"). See more in: http://www.wbabin.net/valev/valev2.pdf Pentcho Valev |
#2
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BEYOND MAXWELL'S DEMON
On Nov 19, 2:07*am, Pentcho Valev wrote:
If a constant-charge parallel-plate capacitor is immersed in water, a pressure develops between the plates that greatly exceeds the pressure outside the capacitor plates. (W. Panofsky, M. Phillips, Classical Electricity and Magnetism, Addison-Wesley, Reading, Massachusetts, 1962, pp. 112-116). If the capacitor plate is very thin, we can imagine a sharp drop in pressure across it; then the following conclusion is unavoidable: Your conclusion is wrong. Punching a small hole in the plate will result in an eternal water flow through the hole, from inside to the outside of the capacitor, in violation of the second law of thermodynamics. This is not an eternal flow of water. This is not a violation of the second law of thermodynamics. A few years ago, at the 2002 First International Conference on Quantum Limits to the Second Law, I called the effect "dynamic equilibrium": http://link.aip.org/link/?APCPCS/643/430/1 "Two testable paradigms - the system performing two types of reversible work and the system in dynamical equilibrium - suggest that perpetuum mobile of the second kind in the presence of an operator is possible." It is not reversible work. There is no heat being transferred. No energy is being transferred by heat conduction. This is not a heat engine any more than an electric motor is a heat engine. An electric current goes in, and the water moves for a short time. However, this is very far from a perpetual flow. Energy is being used up. Electric current is flowing through the water from the socket. The water is heating up in both beakers, not just one. The electric current is heating the water by performing work. The scientific community remained silent and hostile but still from time to time Panofsky-Phillips pressure leaves scientists speechless: Panofsky=Phillips pressure is not a violation of the Second Law of Thermodynamics. http://www.physorg.com/news110191847.html "When exposed to a high-voltage electric field, water in two beakers climbs out of the beakers and crosses empty space to meet, forming the water bridge. The liquid bridge, hovering in space, appears to the human eye to defy gravity." 1) There is no continuous flow of water being demonstrated since the water bridge is just "hovering". If there was continuous flow of water, one beaker would empty and the other fill up. 2) There is an electric current passing through the water bridge. Thus, work is being done on the water. There is no heat flow between the two beakers. One beaker is not heating up while the other is cooling down. 3) The bridge is not perpetual. It falls apart. 4) You are an idiot! |
#3
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BEYOND MAXWELL'S DEMON
What is the probability that Mr. X looks like Mr. Y? Clearly the prior
(Mr. X and Mr. Y are identified but no additional assumption has been made about them) probability is virtually zero. This means that for the argument: Assumption: Mr. X and Mr. Y are identical twins. Conclusion: Mr. X looks like Mr. Y. the combination "false assumption, true conclusion" is virtually impossible. Consider an oversimplified presentation of Carnot's 1824 argument: Assumption: Heat is an indestructible substance (cannot be converted into work in the heat engine). Conclusion (prototype of the second law of thermodynamics): The heat engine X working between the temperatures T1 and T2 is just as efficient as the heat engine Y working between the same temperatures. The assumption turned out to be false in the end. Is the prior probability of the conclusion virtually zero? Is the combination "false assumption, true conclusion" virtually impossible? Clausius managed to convince the world that this combination is a fact in Carnot's argument: http://www.phs.uoa.gr/~psillos/Publi...es/Caloric.pdf "Clausius observed that, despite Carnot's being far from proving the first law of thermodynamics, his theorems were independent of the faulty assumption that no heat is lost in a Carnot cycle." If Carnot's conclusion (the prototype of the second law of thermodynamics) cannot be true, as the analogy with the identical twin scenario suggests, then Clausius' 1850 argument abandoning Carnot's false assumption and deducing the precious conclusion from an alternative assumption, true this time, must be invalid: http://web.lemoyne.edu/~giunta/Clausius.html "Ueber die bewegende Kraft der Wärme" 1850 Rudolf Clausius: "Carnot assumed, as has already been mentioned, that the equivalent of the work done by heat is found in the mere transfer of heat from a hotter to a colder body, while the quantity of heat remains undiminished. The latter part of this assumption--namely, that the quantity of heat remains undiminished--contradicts our former principle, and must therefore be rejected... (...) It is this maximum of work which must be compared with the heat transferred. When this is done it appears that there is in fact ground for asserting, with Carnot, that it depends only on the quantity of the heat transferred and on the temperatures t and tau of the two bodies A and B, but not on the nature of the substance by means of which the work is done. (...) If we now suppose that there are two substances of which the one can produce more work than the other by the transfer of a given amount of heat, or, what comes to the same thing, needs to transfer less heat from A to B to produce a given quantity of work, we may use these two substances alternately by producing work with one of them in the above process. At the end of the operations both bodies are in their original condition; further, the work produced will have exactly counterbalanced the work done, and therefore, by our former principle, the quantity of heat can have neither increased nor diminished. THE ONLY CHANGE will occur in the distribution of the heat, since more heat will be transferred from B to A than from A to B, and so on the whole heat will be transferred from B to A. By repeating these two processes alternately it would be possible, WITHOUT ANY EXPENDITURE OF FORCE OR ANY OTHER CHANGE, to transfer as much heat as we please from a cold to a hot body, and this is not in accord with the other relations of heat, since it always shows a tendency to equalize temperature differences and therefore to pass from hotter to colder bodies." The invalidity of Clausius' 1850 argument comes from an auxiliary false assumption embodied in "THE ONLY CHANGE" and "WITHOUT ANY EXPENDITURE OF FORCE OR ANY OTHER CHANGE". In fact, the two-substances process considered by Clausius presupposes the constant action of an OPERATOR; this operator constantly and unavoidably undergoes CHANGES, changes that are absent when heat spontaneously "shows a tendency to equalize temperature differences and therefore to pass from hotter to colder bodies" (Clausius' alternative true assumption). In other words, the fact that, spontaneously, heat never flows from cold to hot by no means implies that the operator-driven two-substances process considered by Clausius is unable to transfer heat from cold to hot. Pentcho Valev |
#4
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BEYOND MAXWELL'S DEMON
A better reference to Clausius' 1850 argument:
http://www.mdpi.org/lin/clausius/clausius.htm "Ueber die bewegende Kraft der Wärme", 1850, Rudolf Clausius: "Carnot assumed, as has already been mentioned, that the equivalent of the work done by heat is found in the mere transfer of heat from a hotter to a colder body, while the quantity of heat remains undiminished. The latter part of this assumption--namely, that the quantity of heat remains undiminished--contradicts our former principle, and must therefore be rejected... (...) It is this maximum of work which must be compared with the heat transferred. When this is done it appears that there is in fact ground for asserting, with Carnot, that it depends only on the quantity of the heat transferred and on the temperatures t and tau of the two bodies A and B, but not on the nature of the substance by means of which the work is done. (...) If we now suppose that there are two substances of which the one can produce more work than the other by the transfer of a given amount of heat, or, what comes to the same thing, needs to transfer less heat from A to B to produce a given quantity of work, we may use these two substances alternately by producing work with one of them in the above process. At the end of the operations both bodies are in their original condition; further, the work produced will have exactly counterbalanced the work done, and therefore, by our former principle, the quantity of heat can have neither increased nor diminished. The only change will occur in the distribution of the heat, since more heat will be transferred from B to A than from A to B, and so on the whole heat will be transferred from B to A. By repeating these two processes alternately it would be possible, without any expenditure of force or any other change, to transfer as much heat as we please from a cold to a hot body, and this is not in accord with the other relations of heat, since it always shows a tendency to equalize temperature differences and therefore to pass from hotter to colder bodies." Pentcho Valev |
#5
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BEYOND MAXWELL'S DEMON
http://arxiv.org/PS_cache/arxiv/pdf/...009.5394v1.pdf
Hans R. Moser Physics Institute, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland Does the second law of thermodynamics really hold good without exception? Such questions are meaningless in the era of Postscientism where the second law of thermodynamics (version: "Entropy always increases") both holds "the supreme position among the laws of Nature" and "is actually a RED HERRING": http://web.mit.edu/keenansymposium/o...und/index.html Arthur Eddington: "The law that entropy always increases, holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations - then so much the worse for Maxwell's equations. If it is found to be contradicted by observation - well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics, I can give you no hope; there is nothing for it but to collapse in deepest humiliation." http://philsci-archive.pitt.edu/archive/00000313/ Jos Uffink: "Snow stands up for the view that exact science is, in its own right, an essential part of civilisation, and should not merely be valued for its technological applications. Anyone who does not know the Second Law of Thermodynamics, and is proud of it too, exposes oneself as a Philistine. Snow's plea will strike a chord with every physicist who has ever attended a birthday party. But his call for cultural recognition creates obligations too. Before one can claim that acquaintance with the Second Law is as indispensable to a cultural education as Macbeth or Hamlet, it should obviously be clear what this law states. This question is surprisingly difficult. The Second Law made its appearance in physics around 1850, but a half century later it was already surrounded by so much confusion that the British Association for the Advancement of Science decided to appoint a special committee with the task of providing clarity about the meaning of this law. However, its final report (Bryan 1891) did not settle the issue. Half a century later, the physicist/philosopher Bridgman still complained that there are almost as many formulations of the second law as there have been discussions of it (Bridgman 1941, p. 116). And even today, the Second Law remains so obscure that it continues to attract new efforts at clarification. A recent example is the work of Lieb and Yngvason (1999)......The historian of science and mathematician Truesdell made a detailed study of the historical development of thermodynamics in the period 1822-1854. He characterises the theory, even in its present state, as 'a dismal swamp of obscurity' (1980, p. 6) and 'a prime example to show that physicists are not exempt from the madness of crowds' (ibid. p. 8).......Clausius' verbal statement of the second law makes no sense.... All that remains is a Mosaic prohibition ; a century of philosophers and journalists have acclaimed this commandment ; a century of mathematicians have shuddered and averted their eyes from the unclean.....Seven times in the past thirty years have I tried to follow the argument Clausius offers....and seven times has it blanked and gravelled me.... I cannot explain what I cannot understand.....This summary leads to the question whether it is fruitful to see irreversibility or time-asymmetry as the essence of the second law. Is it not more straightforward, in view of the unargued statements of Kelvin, the bold claims of Clausius and the strained attempts of Planck, to give up this idea? I believe that Ehrenfest-Afanassjewa was right in her verdict that the discussion about the arrow of time as expressed in the second law of the thermodynamics is actually a RED HERRING." http://www.liferesearchuniversal.com...html#seventeen George Orwell: "Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously, and accepting both of them. The Party intellectual knows in which direction his memories must be altered; he therefore knows that he is playing tricks with reality; but by the exercise of doublethink he also satisfies himself that reality is not violated. The process has to be conscious, or it would not be carried out with sufficient precision, but it also has to be unconscious, or it would bring with it a feeling of falsity and hence of guilt. Doublethink lies at the very heart of Ingsoc, since the essential act of the Party is to use conscious deception while retaining the firmness of purpose that goes with complete honesty. To tell deliberate lies while genuinely believing in them, to forget any fact that has become inconvenient, and then, when it becomes necessary again, to draw it back from oblivion for just so long as it is needed, to deny the existence of objective reality and all the while to take account of the reality which one denies - all this is indispensably necessary. Even in using the word doublethink it is necessary to exercise doublethink. For by using the word one admits that one is tampering with reality; by a fresh act of doublethink one erases this knowledge ; and so on indefinitely, with the lie always one leap ahead of the truth. (...) It need hardly be said that the subtlest practitioners of doublethink are those who invented doublethink and know that it is a vast system of mental cheating. In our society, those who have the best knowledge of what is happening are also those who are furthest from seeing the world as it is. In general, the greater the understanding, the greater the delusion ; the more intelligent, the less sane." Pentcho Valev |
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