Gaussian Time-Dependent Variational Principle for Bosons I - Uniform Case

Arthur K. Kerman; Paolo Tommasini

doi:10.1006/aphy.1997.5723

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arXiv · cond-mat/9707315

Gaussian Time-Dependent Variational Principle for Bosons I - Uniform Case

Arthur K. Kerman·Paolo Tommasini

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Abstract

We investigate the Dirac time-dependent variational method for a system of non-ideal Bosons interacting through an arbitrary two body potential. The method produces a set of non-linear time dependent equations for the variational parameters. In particular we have considered small oscillations about equilibrium. We obtain generalized RPA equations that can be understood as interacting quasi-bosons, usually mentioned in the literature as having a gap. The result of this interaction provides us with scattering properties of these quasi-bosons including possible bound-states, which can include zero modes. In fact the zero mode bound state can be interpreted as a new quasi-boson with a gapless dispersion relation. Utilizing these results we discuss a straightforward scheme for introducing temperature.

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Arthur K. Kerman, Paolo Tommasini. 1997-07-30. Gaussian Time-Dependent Variational Principle for Bosons I - Uniform Case. https://doi.org/10.1006/aphy.1997.5723

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