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Gaussian Time-Dependent Variational Principle for Bosons

✍ Scribed by Arthur K. Kerman; Paolo Tommasini

Publisher: Elsevier Science
Year: 1997
Tongue: English
Weight: 445 KB
Volume: 260
Category: Article
ISSN: 0003-4916
DOI: 10.1006/aphy.1997.5723

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✦ Synopsis

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 quasibosons 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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