Communications in Theoretical Physics

Deriving Internal Energy by Virtue of Generalized Feynman–Hellmann Theorem for Mixed States

Hong-Yi Fan, Zhonghua Jiang

Published Dec 1, 2005• 1 citation

Abstract

We show how to directly use the generalized Feynman–Hellmann theorem, which is suitable for mixed state ensemble average, to derive the internal energy of Hamiltonian systems. A concrete example, which is a two coupled harminic oscillators, is used for elucidating our approach.

DOI: 10.1088/6102/44/6/1041

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