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arXiv:1605.07386 · Letters in Mathematical Physics

Triviality of a model of particles with point interactions in the thermodynamic limit

Thomas Moser, Robert Seiringer

Published Nov 29, 2016• 2 citations
arXivHTMLPDF

Abstract

We consider a model of fermions interacting via point interactions, defined via a certain weighted Dirichlet form. While for two particles the interaction corresponds to infinite scattering length, the presence of further particles effectively decreases the interaction strength. We show that the model becomes trivial in the thermodynamic limit, in the sense that the free energy density at any given particle density and temperature agrees with the corresponding expression for non-interacting particles.

DOI
10.1007/s11005-016-0915-x

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We consider a model of fermions interacting via point interactions, defined via a certain weighted Dirichlet form. While for two particles the interaction corresponds to infinite scattering length, the presence of further particles effectively decreases the interaction strength. We show that the model becomes trivial in the thermodynamic limit, in the sense that the free energy density at any given particle density and temperature agrees with the corresponding expression for non-interacting particles.
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