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Ground state energy of a homogeneous Bose-Einstein condensate beyond Bogoliubov

Christoph Weiss·Andre Eckardt
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Abstract

The standard calculations of the ground-state energy of a homogeneous Bose gas rely on approximations which are physically reasonable but difficult to control. Lieb and Yngvason [Phys. Rev. Lett. 80, 2504 (1998)] have proved rigorously that the commonly accepted leading order term of the ground state energy is correct in the zero-density-limit. Here, strong indications are given that also the next to leading term is correct. It is shown that the first terms obtained in a perturbative treatment provide contributions which are lost in the Bogoliubov approach.

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Christoph Weiss, Andre Eckardt. 2004-08-02. Ground state energy of a homogeneous Bose-Einstein condensate beyond Bogoliubov. https://doi.org/10.1209/epl%2Fi2004-10169-6

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