On the Hellmann-Feynman theorem in statistical mechanics

Paolo Amore; Francisco M. Fernández

doi:10.1016/j.physleta.2020.126531

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arXiv · 2004.04018

On the Hellmann-Feynman theorem in statistical mechanics

Paolo Amore·Francisco M. Fernández

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Abstract

In this paper we develop the Hellmann-Feynman theorem in statistical mechanics without resorting to the eigenvalues and eigenvectors of the Hamiltonian operator. Present approach does not require the quantum-mechanical version of the theorem at $T=0$ and bypasses any discussion about degenerate states.

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Paolo Amore, Francisco M. Fernández. 2020-04-30. On the Hellmann-Feynman theorem in statistical mechanics. https://doi.org/10.1016/j.physleta.2020.126531

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