dennislmay Posted March 26, 2013 Share Posted March 26, 2013 I wrote [Objectivist Living Room]:"I don't have any issues with thermodynamics - when properly understood. There are however manyclueless physics PhD's and some Nobel laureates out there [past] who have spouted nonsense when it comes to thermodynamics. It is not usually difficult to spot nonsense because it usually comes down to the same few errors."BaalChatzaf wrote:"Could you enumerate the few errors in a separate posting."Error # 1: Not taking the entire system into account [leading to perpetual motion]:Example:A dozen plus PhD's plus graduate students and hundreds of thousands of tax payer dollars spenthttp://link.springer.com/article/10.1023/A%3A1003684421550Published solution:http://www.escholarship.org/uc/item/7zp7k6zp#page-1Summary: A thermodynamic system was created made of colliding particles - they neglected takingthe large body's reaction to each individual collision into account. Rather they attempted to act likethe large body was outside of the system while adding up the collisions and net energy transfers.Error # 2: Substituting continuous functions for discrete functions [loss of information]:Ilya Prigogine:http://en.wikipedia.org/wiki/Indeterminism“Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability.”Prigogine pulled some fast ones claiming irreversibility by illegitimate mathematical substitutions.David Bohm explained in “Wholeness and the Implicate Order” you can’t simply replaceindividual interactions with continuous functions – doing so destroys information content.Error # 3: Faulty Generalization/Straw Man [claiming all situations covered by the Straw Man]:1904 solution to Le Sage gravity thermodynamics:http://en.wikipedia.org/wiki/Le_Sage's_theory_of_gravitation“He [J.J. Thomson] argued that Maxwell's heat problem might be avoided by assuming that the absorbed energy is not be converted into heat, but re-radiated in a still more penetrating form.”The same insight applies to many issues concerning ether theory generally.From the same Wikipedia article:“In 1965 Richard Feynman examined the Fatio/Lesage mechanism, primarily as an example of an attempt to explain a "complicated" physical law (in this case, Newton's inverse-square law of gravity) in terms of simpler primitive operations without the use of complex mathematics, and also as an example of a failed theory. He notes that the mechanism of "bouncing particles" reproduces the inverse-square force law and that "the strangeness of the mathematical relation will be very much reduced", but then remarks that the scheme "does not work", because of the drag it predicts would be experienced by moving bodies, "so that is the end of that theory".”Unfortunately when I attended undergraduate and graduate physics only the Feynman view was discussed [appeal to authority]. In fact I had never heard the J.J. Thomson story until Wikipedia had been around for a number of years though I had research the subject for decades including on Wikipedia.Error # 4: Forgetting to apply the entirety of a thermodynamic law:http://en.wikipedia.org/wiki/Second_law_of_thermodynamics“The second law of thermodynamics states that the entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium —the state of maximum entropy.”The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account.Dennis Link to comment Share on other sites More sharing options...
Brant Gaede Posted March 26, 2013 Share Posted March 26, 2013 The closest we can get in my experience to actual perpetual motion is in our Internet postings. --Brant not a physicist Link to comment Share on other sites More sharing options...
BaalChatzaf Posted March 26, 2013 Share Posted March 26, 2013 I wrote [Objectivist Living Room]:"I don't have any issues with thermodynamics - when properly understood. There are however manyclueless physics PhD's and some Nobel laureates out there [past] who have spouted nonsense when it comes to thermodynamics. It is not usually difficult to spot nonsense because it usually comes down to the same few errors."BaalChatzaf wrote:"Could you enumerate the few errors in a separate posting."Error # 1: Not taking the entire system into account [leading to perpetual motion]:Example:A dozen plus PhD's plus graduate students and hundreds of thousands of tax payer dollars spenthttp://link.springer.com/article/10.1023/A%3A1003684421550Published solution:http://www.escholarship.org/uc/item/7zp7k6zp#page-1Summary: A thermodynamic system was created made of colliding particles - they neglected takingthe large body's reaction to each individual collision into account. Rather they attempted to act likethe large body was outside of the system while adding up the collisions and net energy transfers.Error # 2: Substituting continuous functions for discrete functions [loss of information]:Ilya Prigogine:http://en.wikipedia.org/wiki/Indeterminism“Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability.”Prigogine pulled some fast ones claiming irreversibility by illegitimate mathematical substitutions.David Bohm explained in “Wholeness and the Implicate Order” you can’t simply replaceindividual interactions with continuous functions – doing so destroys information content.Error # 3: Faulty Generalization/Straw Man [claiming all situations covered by the Straw Man]:1904 solution to Le Sage gravity thermodynamics:http://en.wikipedia.org/wiki/Le_Sage's_theory_of_gravitation“He [J.J. Thomson] argued that Maxwell's heat problem might be avoided by assuming that the absorbed energy is not be converted into heat, but re-radiated in a still more penetrating form.”The same insight applies to many issues concerning ether theory generally.From the same Wikipedia article:“In 1965 Richard Feynman examined the Fatio/Lesage mechanism, primarily as an example of an attempt to explain a "complicated" physical law (in this case, Newton's inverse-square law of gravity) in terms of simpler primitive operations without the use of complex mathematics, and also as an example of a failed theory. He notes that the mechanism of "bouncing particles" reproduces the inverse-square force law and that "the strangeness of the mathematical relation will be very much reduced", but then remarks that the scheme "does not work", because of the drag it predicts would be experienced by moving bodies, "so that is the end of that theory".”Unfortunately when I attended undergraduate and graduate physics only the Feynman view was discussed [appeal to authority]. In fact I had never heard the J.J. Thomson story until Wikipedia had been around for a number of years though I had research the subject for decades including on Wikipedia.Error # 4: Forgetting to apply the entirety of a thermodynamic law:http://en.wikipedia.org/wiki/Second_law_of_thermodynamics“The second law of thermodynamics states that the entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium —the state of maximum entropy.”The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account.DennisI have met several physicists in my misspent life. None of them got thermodynamics wrong. Not one.Ba'al Chatzaf Link to comment Share on other sites More sharing options...
We Erred Rand Posted March 26, 2013 Share Posted March 26, 2013 I wrote [Objectivist Living Room]:"I don't have any issues with thermodynamics - when properly understood. There are however manyclueless physics PhD's and some Nobel laureates out there [past] who have spouted nonsense when it comes to thermodynamics. It is not usually difficult to spot nonsense because it usually comes down to the same few errors."BaalChatzaf wrote:"Could you enumerate the few errors in a separate posting."Error # 1: Not taking the entire system into account [leading to perpetual motion]:Example:A dozen plus PhD's plus graduate students and hundreds of thousands of tax payer dollars spenthttp://link.springer.com/article/10.1023/A%3A1003684421550Published solution:http://www.escholarship.org/uc/item/7zp7k6zp#page-1Summary: A thermodynamic system was created made of colliding particles - they neglected takingthe large body's reaction to each individual collision into account. Rather they attempted to act likethe large body was outside of the system while adding up the collisions and net energy transfers.Error # 2: Substituting continuous functions for discrete functions [loss of information]:Ilya Prigogine:http://en.wikipedia.org/wiki/Indeterminism“Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability.”Prigogine pulled some fast ones claiming irreversibility by illegitimate mathematical substitutions.David Bohm explained in “Wholeness and the Implicate Order” you can’t simply replaceindividual interactions with continuous functions – doing so destroys information content.Error # 3: Faulty Generalization/Straw Man [claiming all situations covered by the Straw Man]:1904 solution to Le Sage gravity thermodynamics:http://en.wikipedia.org/wiki/Le_Sage's_theory_of_gravitation“He [J.J. Thomson] argued that Maxwell's heat problem might be avoided by assuming that the absorbed energy is not be converted into heat, but re-radiated in a still more penetrating form.”The same insight applies to many issues concerning ether theory generally.From the same Wikipedia article:“In 1965 Richard Feynman examined the Fatio/Lesage mechanism, primarily as an example of an attempt to explain a "complicated" physical law (in this case, Newton's inverse-square law of gravity) in terms of simpler primitive operations without the use of complex mathematics, and also as an example of a failed theory. He notes that the mechanism of "bouncing particles" reproduces the inverse-square force law and that "the strangeness of the mathematical relation will be very much reduced", but then remarks that the scheme "does not work", because of the drag it predicts would be experienced by moving bodies, "so that is the end of that theory".”Unfortunately when I attended undergraduate and graduate physics only the Feynman view was discussed [appeal to authority]. In fact I had never heard the J.J. Thomson story until Wikipedia had been around for a number of years though I had research the subject for decades including on Wikipedia.Error # 4: Forgetting to apply the entirety of a thermodynamic law:http://en.wikipedia.org/wiki/Second_law_of_thermodynamics“The second law of thermodynamics states that the entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium —the state of maximum entropy.”The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account.Dennis>>>>The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account. I think the 2nd Law is more clearly conceptualized in its statistical-mechanics version as referring to the probability of certain spatial configurations of particles. The 2nd Law confidently predicts that configurations always move from states of lower probability to those of higher probability within an isolated system. However (and this is a big "however"), the 2nd Law does NOT say that simply because one opens the barrier between the isolated system and some larger system encompassing it, that configurations "must", or "shall", move from states of high probability to states of lower probability. There's no inevitability about it. Configurations "MIGHT" or "MAY" move from high-to-low probability, given the additional resources of the enlarged (so-called "open") system. I state the obvious only because many people mistakenly assume that an enlarged system gives them "poetic license", so to speak, to invoke miracles when convenient for their hypotheses. It usually takes the form of saying, "Of course my scenario could work. All it requires is an open system!" And voila! all problems are (supposedly) solved. I always ask them, "What makes you so sure that only 'benevolent', constructive forces will enter your previously closed system leading to states of lower probability? Why wouldn't your putative open system also contribute additional destructive elements as well?" They never have an answer. For them, simply having an enlarged pool, or resource, of energy available automatically leads to constructive processes rather than additional destructive ones.In sum: the 2nd Law does not state that "anything you want to imagine is possible so long as there's an open system." Link to comment Share on other sites More sharing options...
dennislmay Posted March 26, 2013 Author Share Posted March 26, 2013 I wrote [Objectivist Living Room]:"I don't have any issues with thermodynamics - when properly understood. There are however manyclueless physics PhD's and some Nobel laureates out there [past] who have spouted nonsense when it comes to thermodynamics. It is not usually difficult to spot nonsense because it usually comes down to the same few errors."BaalChatzaf wrote:"Could you enumerate the few errors in a separate posting."Error # 1: Not taking the entire system into account [leading to perpetual motion]:Example:A dozen plus PhD's plus graduate students and hundreds of thousands of tax payer dollars spenthttp://link.springer.com/article/10.1023/A%3A1003684421550Published solution:http://www.escholarship.org/uc/item/7zp7k6zp#page-1Summary: A thermodynamic system was created made of colliding particles - they neglected takingthe large body's reaction to each individual collision into account. Rather they attempted to act likethe large body was outside of the system while adding up the collisions and net energy transfers.Error # 2: Substituting continuous functions for discrete functions [loss of information]:Ilya Prigogine:http://en.wikipedia.org/wiki/Indeterminism“Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability.”Prigogine pulled some fast ones claiming irreversibility by illegitimate mathematical substitutions.David Bohm explained in “Wholeness and the Implicate Order” you can’t simply replaceindividual interactions with continuous functions – doing so destroys information content.Error # 3: Faulty Generalization/Straw Man [claiming all situations covered by the Straw Man]:1904 solution to Le Sage gravity thermodynamics:http://en.wikipedia.org/wiki/Le_Sage's_theory_of_gravitation“He [J.J. Thomson] argued that Maxwell's heat problem might be avoided by assuming that the absorbed energy is not be converted into heat, but re-radiated in a still more penetrating form.”The same insight applies to many issues concerning ether theory generally.From the same Wikipedia article:“In 1965 Richard Feynman examined the Fatio/Lesage mechanism, primarily as an example of an attempt to explain a "complicated" physical law (in this case, Newton's inverse-square law of gravity) in terms of simpler primitive operations without the use of complex mathematics, and also as an example of a failed theory. He notes that the mechanism of "bouncing particles" reproduces the inverse-square force law and that "the strangeness of the mathematical relation will be very much reduced", but then remarks that the scheme "does not work", because of the drag it predicts would be experienced by moving bodies, "so that is the end of that theory".”Unfortunately when I attended undergraduate and graduate physics only the Feynman view was discussed [appeal to authority]. In fact I had never heard the J.J. Thomson story until Wikipedia had been around for a number of years though I had research the subject for decades including on Wikipedia.Error # 4: Forgetting to apply the entirety of a thermodynamic law:http://en.wikipedia.org/wiki/Second_law_of_thermodynamics“The second law of thermodynamics states that the entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium —the state of maximum entropy.”The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account.Dennis>>>>The key word in this is “isolated”. The 2nd law is invoked incorrectly in many situationsbecause the entire context of the law is not taken into account. I think the 2nd Law is more clearly conceptualized in its statistical-mechanics version as referring to the probability of certain spatial configurations of particles. The 2nd Law confidently predicts that configurations always move from states of lower probability to those of higher probability within an isolated system. However (and this is a big "however"), the 2nd Law does NOT say that simply because one opens the barrier between the isolated system and some larger system encompassing it, that configurations "must", or "shall", move from states of high probability to states of lower probability. There's no inevitability about it. Configurations "MIGHT" or "MAY" move from high-to-low probability, given the additional resources of the enlarged (so-called "open") system. I state the obvious only because many people mistakenly assume that an enlarged system gives them "poetic license", so to speak, to invoke miracles when convenient for their hypotheses. It usually takes the form of saying, "Of course my scenario could work. All it requires is an open system!" And voila! all problems are (supposedly) solved. I always ask them, "What makes you so sure that only 'benevolent', constructive forces will enter your previously closed system leading to states of lower probability? Why wouldn't your putative open system also contribute additional destructive elements as well?" They never have an answer. For them, simply having an enlarged pool, or resource, of energy available automatically leads to constructive processes rather than additional destructive ones.In sum: the 2nd Law does not state that "anything you want to imagine is possible so long as there's an open system."Quite correct, I was not attempting to open thermodynamics up for obvious abuse. I am more concerned about numerous popular pronouncements concerning entropy that do no apply to open systems - yet the pronouncers always neglect to mention the exceptions or under what boundry conditions their pronouncements are valid. This has lead to generations of students being misinformed [and you still see the problem at the PhD level] concerning such pronouncements. Repetition of mistakes - never corrected - become fact to those who don't take the time to understand what is really being claimed.Dennis Link to comment Share on other sites More sharing options...
PDS Posted March 28, 2013 Share Posted March 28, 2013 The closest we can get in my experience to actual perpetual motion is in our Internet postings.--Brantnot a physicistBrant:Great to see you back in your finest of form. This ranks among the best of your bon mots. Link to comment Share on other sites More sharing options...
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