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arXiv · 1301.3942

On two dimensional non-abelian chiral lattice gauge theories in Ginsparg-Wilson formalism

Yanwen Shang
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Abstract

Defining chiral lattice gauge theories in the Ginsparg-Wilson formalism is complicated by the so-called fermion measure problem. It has been proven for the abelian theories that smooth well-behaved fermion measure exists if and only if the anomaly-free condition is granted, and the same was shown to hold in perturbative theories for non-abelian gauge groups, but the non-perturbative proof is absent. In this paper, we consider a simpler problem in 2-d and present a proof for the existence of smooth and gauge invariant fermion measure on the gauge field configuration space with zero field strengths for arbitrary compact Lie groups, provided the anomaly-free conditions are satisfied. It is conjectured that such consideration is sufficient for the unknown full proof.

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Yanwen Shang. 2013-04-10. On two dimensional non-abelian chiral lattice gauge theories in Ginsparg-Wilson formalism. https://arxiv.org/abs/1301.3942

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