Exchanging roles of variable and thermal potential

AI Thread Summary
In thermal physics, entropy (S) is a key variable in the first theorem of thermodynamics, relating energy changes to entropy and volume. The discussion explores whether other variables like volume (V), pressure (p), and temperature (T) can also be considered thermal potentials, similar to entropy. It questions if the exchange of roles between variables and thermal potentials is limited to the pair of energy (E) and entropy (S). The equations provided suggest that V, T, and p can indeed function as thermal potentials. Overall, the inquiry seeks to clarify the broader applicability of thermal potentials beyond just entropy.
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In thermal physics entropy S is regarded as a system variable in 1st theorem of thermal dynamics, i.e.
dE(S,V)=TdS-pdV=T(S,V)dS-p(S,V)dV

Entropy is regarded also as thermal potential,i.e.

dS(E,V)=\frac{1}{T(E,V)}dE + \frac{p(E,V)}{T(E,V)}dV

S,V,p,T are usually regarded as variables. My question is that other variables V, p, T can be also treated as thermal potentials ? Can exchanging roles of variable and thermal potential take place only for the pair of E and S ?
 
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dV(S,E)=\frac{T(S,E)}{p(S,E)}dS-\frac{1}{p(S,E)}dE
dT(F,V)=\frac{p(F,V)}{S(F,V)}dV-\frac{1}{S(F,V)}dF
dp(G,T)=\frac{1}{V(G,T)}dG+\frac{S(G,T)}{V(G,T)}dT
where
F=E-TS
G=E-TS+PV

V,T and p are thermal potential as S is. Is it OK?
 
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