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arXiv · 1905.00137

Absence of chiral symmetry breaking in Thirring models in 1+2 dimensions

Julian Lenz·Björn Wellegehausen·Andreas Wipf
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Abstract

The Thirring model is an interacting fermion theory with current-current interaction. The model in $1+2$ dimensions has applications in condensed-matter physics to describe the electronic excitations of Dirac materials. Earlier investigations with Schwinger-Dyson equations, the functional renormalization group and lattice simulations with staggered fermions suggest that a critical number of (reducible) flavors $N^{\mathrm{c}}$ exists, below which chiral symmetry can be broken spontaneously. Values for $N^{\mathrm{c}}$ found in the literature vary between $2$ and $7$. Recent lattice studies with chirally invariant SLAC fermions have indicated that chiral symmetry is unbroken for all integer flavor numbers [Wellegehausen et al., 2017]. An independent simulation based on domain wall fermions seems to favor a critical flavor-number that satisfies $1 N^{\mathrm{c}}$ and should answer the question of where to construct a continuum limit.

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Julian Lenz, Björn Wellegehausen, Andreas Wipf. 2019-05-22. Absence of chiral symmetry breaking in Thirring models in 1+2 dimensions. https://doi.org/10.1103/physrevd.100.054501

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