Thermodynamics - Properly Understood


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I wrote [Objectivist Living Room]:

"I don't have any issues with thermodynamics - when properly understood. There are however many

clueless 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 spent

http://link.springer.com/article/10.1023/A%3A1003684421550

Published solution:

http://www.escholarship.org/uc/item/7zp7k6zp#page-1

Summary: A thermodynamic system was created made of colliding particles - they neglected taking

the large body's reaction to each individual collision into account. Rather they attempted to act like

the 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 replace

individual 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 situations

because the entire context of the law is not taken into account.


Dennis

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I wrote [Objectivist Living Room]:

"I don't have any issues with thermodynamics - when properly understood. There are however many

clueless 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 spent

http://link.springer.com/article/10.1023/A%3A1003684421550

Published solution:

http://www.escholarship.org/uc/item/7zp7k6zp#page-1

Summary: A thermodynamic system was created made of colliding particles - they neglected taking

the large body's reaction to each individual collision into account. Rather they attempted to act like

the 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 replace

individual 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 situations

because the entire context of the law is not taken into account.

Dennis

I have met several physicists in my misspent life. None of them got thermodynamics wrong. Not one.

Ba'al Chatzaf

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I wrote [Objectivist Living Room]:

"I don't have any issues with thermodynamics - when properly understood. There are however many

clueless 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 spent

http://link.springer.com/article/10.1023/A%3A1003684421550

Published solution:

http://www.escholarship.org/uc/item/7zp7k6zp#page-1

Summary: A thermodynamic system was created made of colliding particles - they neglected taking

the large body's reaction to each individual collision into account. Rather they attempted to act like

the 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 replace

individual 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 situations

because 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 situations

because 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."

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I wrote [Objectivist Living Room]:

"I don't have any issues with thermodynamics - when properly understood. There are however many

clueless 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 spent

http://link.springer.com/article/10.1023/A%3A1003684421550

Published solution:

http://www.escholarship.org/uc/item/7zp7k6zp#page-1

Summary: A thermodynamic system was created made of colliding particles - they neglected taking

the large body's reaction to each individual collision into account. Rather they attempted to act like

the 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 replace

individual 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 situations

because 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 situations

because 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

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The closest we can get in my experience to actual perpetual motion is in our Internet postings.

--Brant

not a physicist

Brant:

Great to see you back in your finest of form. This ranks among the best of your bon mots.

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