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Superfluidity in a Model of Massless Fermions Coupled to Scalar Bosons

R. D. Pisarski·D. H. Rischke
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Abstract

We study superfluidity in a model of massless fermions coupled to a massive scalar field through a Yukawa interaction. Gap equations for a condensate with total spin J=0 are solved in the mean-field approximation. For the Yukawa interaction, the gaps for right- and left-handed fermions are equal in magnitude and opposite in sign, so that condensation occurs in the J^P = 0^+ channel. At finite scalar mass, there are two different gaps for fermions of a given chirality, corresponding to condensation of particle pairs or of antiparticle pairs. These gaps become degenerate in the limit of infinite scalar mass.

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R. D. Pisarski, D. H. Rischke. 1999-06-18. Superfluidity in a Model of Massless Fermions Coupled to Scalar Bosons. https://doi.org/10.1103/physrevd.60.094013

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