Lagrangian mechanics and thermodynamics

AI Thread Summary
The discussion explores the potential relationship between Lagrangian mechanics and thermodynamics, specifically regarding Hamiltonian and thermodynamic potentials like Gibbs free energy and enthalpy. It raises the question of whether the principle of least action in mechanics parallels the principle of minimum energy at constant entropy in thermodynamics. Participants note that there is indeed a connection through statistical thermodynamics, which links classical thermodynamic results to statistical mechanics principles. The Hamiltonian formalism is emphasized as a foundational aspect in both quantum mechanics and statistical mechanics. Overall, the inquiry highlights the intriguing interplay between these two areas of physics.
Feynmanfan
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Dear friends,

After having studied thermodynamics for some months as well as Lagrangian mechanics, I'm trying to find a relationship between the Hamiltonian, Lagrangian, conjugated potentials etc. and thermodynamic potentials (such as Gibbs free energy, Enthalpy etc.).

I mean, they may have nothing to do with each other but I'm sure there's an analogy. I've learned to do Legendre's transformations in both fields!

Is The analogous of the principle of least action the principle of minimum energy at constant entropy?

I don't know if it's a waste of time trying to find a conexion.

Happy new year!
 
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To your knowledge,there is a connection between the Hamiltonian (classical or quantum) and thermodynamic quantities which is realized in statistical thermodynamics,which is a subtheory of statistical mechanics who finds the well known results from classical thermodynamics starting from statistical mechanics principles.
Usually,statistical mechanics is built in the Hamilton formalism,just as QM is built in the Hamilton formalism.

Daniel.
 
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