Mean energy of some interacting bosonic systems derived by virtue of the generalized Hellmann–Feynman theorem
Hong-Yi Fan, Xue-xiang Xu · Journal of Mathematical Physics · 2009
By virtue of the generalized Hellmann–Feynman theorem [H. Y. Fan and B. Z. Chen, Phys. Lett. A 203, 95 (1995)], we derive the mean energy of some interacting bosonic systems for some Hamiltonian models without proceeding with diagonalizing the Hamiltonians. Our work extends the field of applications of the Hellmann–Feynman theorem and may enrich the theory of quantum statistics.