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On the 'Strong-Coupling' Generalization of the Bogoliubov Model

A. Yu. Cherny·A. A. Shanenko
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Abstract

A generalized Bogoliubov model of the Bose gas in the ground state is proposed which properly takes into account both the long-range and short-range spatial boson correlations. It concerns equilibrium characteristics and operates with in-medium Schrodinger equations for the pair wave functions of bosons being the eigenfunctions of the second-order reduced density matrix. The approach developed provides reasonable results for a dilute Bose gas with arbitrary strong interaction between particles (the 'strong-coupling' case) and comes to the canonical Bogoliubov model in the weak-coupling regime.

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A. Yu. Cherny, A. A. Shanenko. 1999-04-14. On the 'Strong-Coupling' Generalization of the Bogoliubov Model. https://doi.org/10.1016/s0375-9601(98)00835-4

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