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A Soluble Model of Four-Fermion Interactions in de Sitter Space

T. Inagaki·S. Mukaigawa·T. Muta
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Abstract

We consider the theory of four-fermion interactions with N-component fermions in de Sitter space. It is found that the effective potential for a composite operator in the theory is calculable in the leading order of the 1/N expansion. The resulting effective potential is analyzed by varying both the four-fermion coupling constant and the curvature of the space-time. The critical curvature at which the dynamically generated fermion mass disappears is found to exist and is calculated analytically. The dynamical fermion mass is expressed as a function of the space-time curvature.

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T. Inagaki, S. Mukaigawa, T. Muta. 1995-05-11. A Soluble Model of Four-Fermion Interactions in de Sitter Space. https://doi.org/10.1103/physrevd.52.r4267

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