Talk:Philosophy of thermal and statistical physics

Merge

I think all of this pages content can be incorporated into the thermodynamics article. Perhaps this page should not be deleted, but dedicated to explaining the link between thermodynamics and statistical mechanics. As it stands, it could use some work in that area. PAR 01:05, 17 November 2005 (UTC)

Importance

The link between thermodynamics and statistical mechanics is important because it raises philosophical questions about how the postulatory method is used in science. There are questions raised about how humans "do" science, and how different subfields use the same words to mean the same thing, but with different implicit assumptions that are only assumed by those in the same subfield when they use language in a slightly sloppy way (which is the way it's usually used) or math in a slightly sloppy way (which happpens sometimes too). For example: which is a better way to approach thinking about the laws of nature? Determining a property of matter relative to a perfect vacuum at a temperature of 0 K which can only be approached or determining a property of a system relative to static equilibrium with an infinite reservoir which can only be approached? This is a philosophical question because the two ways will give the same answers if rigor is maintained. But the choice is still made very often in a subconscious way in the mind of researchers in different fields and this choice has conseqeunces that often prevent scientists in different fields from understanding each other. This is not addressed in the present article, so I understand your suggestion for a merge. I am changing the merge tag to an importance tag and adding an expert tag here. We need a systems ecologist who is really great at physics or a physicist who has really dived into the systems ecology literature or a person familiar with both along with issues in the philosophy of science. In a few weeks, I might be familiar enough with the topic to do a major rewrite of this article or move some of what I'm trying to do at exergy here. Flying Jazz 15:22, 10 January 2006 (UTC)

Talk

There is a lot to say about this subject, but it has not yet been said in the Wikipedia. My suggestion is to make this an introduction with links to articles concering detailed subjects. Those articles till have to be written, though. A few suggestions (please feel free to see this as a 'to do' list):

• Status of the 0th law of thermodynamics
• Status of the 1st law of t.
• Status of the 2nd law of t. - this is long and tricky one
• Boltzmann's H-theorem
  • Loschmidt's Umkehreinwand
  • Zermelo's Wiederkehreinwand
• Maxwell's two derivations of his distribution
• Boltzmann's derivation of the MB-distribution
  • Stosszahlansatz
• Ergodic hypothesis
  • Ehrenfest's Quasi-ergodic hypothesis
  • Von Neumann's ergodic theorem
• Markovianism
• Interpretation of statistical ensembles
  • Tolman & Jaynes: subjective interpretation -- Article currently (Nov 05) basically presents subjective view. Tolman also stressed need for ergodicity or quasi-ergodicity; article downplays this. Jheald 21:55, 6 November 2005 (UTC)
• Interpretation of probability -- Jaynes/Bayesian view of entropies & probabilities set out at MaxEnt thermodynamics Jheald 21:55, 6 November 2005 (UTC)
• Maxwell's demon
  • Connection with information theory - hinted at on that page Jheald 21:55, 6 November 2005 (UTC)
    • Szilard
    • Landauer -- some material at Reversible computing Jheald 21:55, 6 November 2005 (UTC)
    • Criticism (Earman & Norton comes to mind)
• Perpetuum mobiles

Etcetera. We have a lot of work to do. ;) -- Victor Gijsbers

Sounds good. I agree, there's certainly a lot of interesting material to be written. You might want to check out our article naming conventions before you start on a large set of articles. -- Tim Starling 14:49 6 Jul 2003 (UTC)

Ah, the capitals. Thanks for mentioning it. -- Victor Gijsbers

You guys seem to have been off to a good start two years ago but to since have abandoned this project. Ah, but I'm on the case now. --Christofurio 13:31, Mar 25, 2005 (UTC)

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WRT the claim of Maxwell's Demon being "refuted", this has only been shown to be the case where the demon is tautologically assumed to be measuring the state of particles through some method which increases overall entropy. I believe I was made aware of this while reading a "This Week's Finds" by John Baez about Huw Price and the arrow of time, but it's also fairly obvious when you consider that it is at least possible to construct a closed system with a "demon" that happens to decrease entropy without measuring any particles (for instance, the universe running in reverse). How do we know our own universe will not eventually decrease in entropy, as Hawking once proposed it might? I imagine this harder to rule out completely than by building several examples of "demons" which fail to live up to the name.

Hm, it looks like there are great references on the page about Maxwell's Demon which can be imported and which contradict the information on this page. I'm too much of a newbie to do it right, though. 76.109.111.75 (talk) 10:38, 1 October 2010 (UTC)

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I'm removing this paragraph, for the following reasons:

• Even if the universe has zero net energy density, that is an empirical observation, not a constraint imposed by the first law of thermodynamics.
• The content of the paragraph is out of date, since it does not mention the cosmological constant, which is now believed to be an important contribution to the energy density of the universe.

Removed text:

"In scientific arguments about cosmology, the study of the cosmos as a whole, this first law is an important constraint - it limits the net energy of universe by zero. Observations indeed support that positive rest energy of matter in visible universe (which amounts to about $10^{70}$ Joules) is equilibrated by the same amount of negative gravitational energy of interaction of this matter (which amounts to the same $10^{70}$ Joules, but with negative sign as gravity is an attractive force). Also, according to cosmological models space-time of zero-energy universe must be flat - and recent observations support this too."

I'm also removing the last part of this paragraph:

"There is, for example, Boltzmann's H-theorem, an interpretation associated with Ludwig Boltzmann (1844 - 1906) which proposes that the directionality of thermodynamics is a consequence of the dimensionality of electromagnetics. Disorderliness, or entropy, must increase over time, in other words, under the influence of time-delayed interactions through purely retarded potentials."

To begin with, the "dimensionality of electromagnetics" has nothing to do with the H theorem. Nor can the retarded potential in electromagnetism explain the directionality of time, since the advanced potential is equally a solution of Maxwell's equations.

67.186.28.212 15:59, 10 September 2005 (UTC)

What is the point of this article?

This article does not discuss the philosophy of thermodynamics, it just gives a brief summary of the laws of thermodynamics. The only part that can be argued to be on topic is the discussion of Maxwell's demon, which already has its own article.

Unless some secondary literature is presented that explicitly addresses the topic of this article, it should be merged or deleted. --dab (𒁳) 12:28, 30 December 2010 (UTC)

I agree. Any material that is of value here could be merged elsewhere. EdJohnston (talk) 14:08, 30 December 2010 (UTC)

I also agree. Perhaps an article of this title is needed, but it would better be written from scratch than as a rescue of the present version. At present there is little or nothing in this article that is not covered adequately in other Wikipedia articles, I think.Chjoaygame (talk) 04:50, 10 February 2016 (UTC)

undid edit; reason

I undid this edit. I don't have immediate access to the cited work, but still the edit as a whole isn't right. The versions were not, I think (subject to correction), first proposed by R.L. Park. I think he reported that wags proposed them. Someone who has access to the book may check this out before I do. Quite possibly the book can be cited, for the statement that R.L. Park reported the wags' version. It would be great if someone could find a real origin for the versions.Chjoaygame (talk) 04:43, 10 February 2016 (UTC)