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arXiv · 1903.03284

Identities and Many-Body Approaches in Bose-Einstein Condensates

Shohei Watabe
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Abstract

This paper discusses exact relations in Bose--Einstein condensates (BECs), starting from basic properties of an ideal Bose gas. In particular, focused on are the Hugenholtz--Pines relation, Nepomnyashchii--Nepomnyashchii identity, and identities for the density response function. After introducing these exact relations, a few approaches of many-body approximations are discussed, which satisfy the exact relations in BECs. This paper will serve as a bridge between theories on exact relations and those on approximations in BECs.

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Shohei Watabe. 2019-07-24. Identities and Many-Body Approaches in Bose-Einstein Condensates. https://doi.org/10.12693/aphyspola.135.1222

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