A note on the calculation of the long-wavelength limit of the bosonic excitation spectrum

Andrij Rovenchak

doi:10.1515/zna-2014-0211

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arXiv · 1405.6839

A note on the calculation of the long-wavelength limit of the bosonic excitation spectrum

Andrij Rovenchak

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Abstract

An approach is proposed to analyze an interacting bosonic system using two-time temperature Green's functions on the collective variables. Two systems are studied: liquid helium-4 and the Yukawa Bose-liquid being a model of the nuclear matter. The suggested decoupling in the equations of motion for Green's functions yields a good description of the elementary excitation spectrum in the long-wavelength limit.

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Andrij Rovenchak. 2014-05-27. A note on the calculation of the long-wavelength limit of the bosonic excitation spectrum. https://doi.org/10.1515/zna-2014-0211

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