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arXiv · 2105.09643

Planar Thirring Model in the U(2$N$)-symmetric limit

Simon Hands
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Abstract

I review the Thirring model in 2+1$d$ dimensions, focussing in particular on possible strongly-interacting UV-stable fixed points of the renormalisation group, corresponding to a continuous phase transition where a U($2N$) global symmetry spontaneously breaks to U($N)\otimes$U($N$). Since there is no small parameter in play, a systematic non-perturbative approach such as numerical simulation of lattice field theory is mandated. I compare and contrast various formulations, paying particular attention to models formulated with either staggered or domain wall lattice fermions. Domain wall fermions, which faithfully capture U($2N$) symmetry in the limit of wall separation $L_s\to\infty$, predict a critical flavor number $1<N_c<2$.

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Simon Hands. 2021-05-20. Planar Thirring Model in the U(2$N$)-symmetric limit. https://arxiv.org/abs/2105.09643

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