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arXiv · 1710.08137

Phases of a strongly coupled four-fermion theory

David Schaich·Simon Catterall
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Abstract

We present ongoing investigations of a four-dimensional lattice field theory with four massless reduced staggered fermions coupled through an SU(4)-invariant four-fermion interaction. As in previous studies of four-fermion and Higgs--Yukawa models with different lattice fermion discretizations, we observe a strong-coupling phase in which the system develops a mass gap without breaking any lattice symmetry. This symmetric strong-coupling phase is separated from the symmetric weak-coupling phase by a narrow region of four-fermi coupling in which the system exhibits long-range correlations.

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David Schaich, Simon Catterall. 2017-10-23. Phases of a strongly coupled four-fermion theory. https://doi.org/10.1051/epjconf%2F201817503004

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