Sum Rules and Bose-Einstein Condensation

S. Stringari

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Sum Rules and Bose-Einstein Condensation

S. Stringari

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Abstract

Various sum rules accounting for the coupling between density and particle excitations and emphasizing in an explicit way the role of the Bose-Einstein condensation are discussed. Important consequences on the fluctuations of the particle operator as well as on the structure of elementary excitations are reviewed. These include a recent generalization of the Hohenberg-Mermin-Wagner theorem holding at zero temperature. (To appear in "Bose-Einstein Condensation", A.Griffin, D.Snoke and S.Stringari eds., Cambridge Univ. Press)

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S. Stringari. 1993-11-10. Sum Rules and Bose-Einstein Condensation. https://arxiv.org/abs/cond-mat/9311024

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