# Talk:Thermodynamic potential

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## Landau Potential

The person that added this to the top of the article should also have modified the parts of the text that talk about the four common thermodynamic potentials, because now there are five equations. Why don't we just list all the energy potentials? I think there are only eight of them.ChrisChiasson 12:47, 9 October 2007 (UTC)

Also, it appears that the present form of the Landau potential does not take into account the possibility of multiple species (since it lists only one chemical potential). ChrisChiasson 06:46, 23 October 2007 (UTC)

## Merging Overview

Regarding the merging of of the thermodynamic potentials section from the thermodynamics page - I think a paragraph or two for someone wanting to get an overview is appropriate, then they can link to this main article for a more in-depth explanation. PAR 22:15, 8 November 2005 (UTC)

## Recent edit

I removed the section that was added, because I think it was just pulled from the thermodynamics article, and it doesn't fit.

• There are no "above differential forms"
• the notation using E has never been introduced
• thermodynamics stands more or less alone as a discipline, It does not need statistical mechanics to justify it or to derive any of its results, only to explain its results from a microscopic viewpoint.
• It is important not to get statistical mechanics and thermodynamics all jumbled up. Any discussion of this fact should go on the thermodynamics page. PAR 12:45, 29 November 2005 (UTC)

## Second Law error?

I think the statements this article makes about the second law might be wrong because there is no mention that the temperature in the first statement is the temperature of the surroundings and not the system. Flying Jazz 04:40, 3 January 2006 (UTC)

## Style of Introduction

The introduction is good (especially when compared with other articles around this topic) but is weakened by the words "in a sense,". For this sort of article we need positive statements. If the author has reservations about this assertion we should at least be told what the other "senses" are.

I move we remove the words "in a sense,". It still stands as a correct and meaniningful statement.

Overall the style is clear and is way ahead of the "entropy" articles which are long on jargon and short on clear defintions. PAS 22:53, 27 February 2007 (UTC)

I have modified the introduction and deleted the words "in a sense" but I have also made some other changes. In particular, I found the use of the word "parameters" and the associated link misleading. I understand this was meant to make it more accessible to the general public, but the word "function" is more correct and I think equally simple. I also added the important fact that all material properties at equilibrium could be derived from the potential (which is I think where the word "potential" comes from). Now, I am not a native speaker and I hope the sentences are not too clumsy. Tizeff 10:52, 28 October 2007 (UTC)

## Mnemonic device

What is the "square" and how should it be used? It doesn't appear to be mentioned in the article. 192.102.214.6

Orphaned text removed (below). Would be logically placed in Maxwell relations, except it's not obviously related to that text either... 84.92.241.186 16:53, 22 October 2007 (UTC)
A mnemonic used by physics students to remember the Maxwell relations in thermodynamics is "Good Physicists Have Studied Under Very Fine Teachers", which helps them remember the order of the variables in the square, in clockwise direction. Another mnemonic used here is "Valid Facts and Theoretical Understanding Generate Solutions to Hard Problems", which gives the letter in the normal left to right writing direction. Both times A has to be identified with F (which is another common symbol for Helmholtz' Free Energy).
I have noted this in the thermodynamic square article. David Hollman (Talk) 14:29, 2 September 2010 (UTC)

## S(U,V,N)

The entropy S(U,V,N) is also referred to as a thermodynamic potential. Not only the thermodynamic potential one get when performing a legendere transformation are thermodynamic potentials. I can provide a german theoretical physics book as reference: Grundkurs Theoretische Physik 4: Spezielle Relativitätstheorie, Thermodynamik page 230 et seqq. Maybe there is an english version of this book. --Biggerj1 (talk) 09:56, 30 July 2013 (UTC)

## Gravity

I wonder if there is a need to include a negligible [gravitational potential energy] at the introduction. It seems to me it only makes it confusing without the need. Felipebm (talk) 12:29, 6 February 2014 (UTC)

## Definition of thermodinamic potentials

It is incorrect to compare thermodinamic potentials with gravity or similar because gravity actually is the energy while thermodinamics potentials are mathematical definition that only in particular conditions represent energies. It is ok to give the idea of what they represent but very confusing to declare them as definitions. I think i'll correct in the text soon. — Preceding unsigned comment added by 151.16.181.249 (talk) 09:29, 19 May 2018 (UTC)

I don't think so. Thermodynamic potentials ${\displaystyle F,G,H,U,\Omega }$ are energies as any other energy (e.g. kinetic, potential) in physics. Terminologically, there are not potentials - they are energies[1]. They are well defined for any system in equilibrium, as well as other extensive state functions ${\displaystyle S,V}$, whereas intensive ones ${\displaystyle T,P,\rho }$ under external field , even homogeneous like gravity ${\displaystyle g}$, should be considered rather locally having in equilibrium different values in different places far enough from each other (see standard thermodynamic models of Earth atmosphere). I think no change nee to be made concerning this problem. --JOb 20:22, 19 May 2018 (UTC) — Preceding unsigned comment added by JOb (talkcontribs)

1. ^ ISO 80000-5, Quantities an units, Part 5 - Thermodynamics, items 5-20.4 Helmholtz energy or function, 5-20.5, Gibbs energy or function