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arXiv · 2010.03595

Two-term expansion of the ground state one-body density matrix of a mean-field Bose gas

Phan Thành Nam·Marcin Napiórkowski
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Abstract

We consider the homogeneous Bose gas on a unit torus in the mean-field regime when the interaction strength is proportional to the inverse of the particle number. In the limit when the number of particles becomes large, we derive a two-term expansion of the one-body density matrix of the ground state. The proof is based on a cubic correction to Bogoliubov's approximation of the ground state energy and the ground state.

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Phan Thành Nam, Marcin Napiórkowski. 2020-10-07. Two-term expansion of the ground state one-body density matrix of a mean-field Bose gas. https://doi.org/10.1007/s00526-021-01954-2

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