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arXiv · 1908.07476

Topological effects in continuum 2d $U(N)$ gauge theories

Claudio Bonati·Paolo Rossi
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Abstract

We study the $θ$ dependence of the continuum limit of 2d $U(N)$ gauge theories defined on compact manifolds, with special emphasis on spherical ($g=0$) and toroidal ($g=1$) topologies. We find that the coupling between $U(1)$ and $SU(N)$ degrees of freedom survives the continuum limit, leading to observable deviations of the continuum topological susceptibility from the $U(1)$ behavior, especially for $g=0$, in which case deviations remain even in the large $N$ limit.

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Claudio Bonati, Paolo Rossi. 2019-08-20. Topological effects in continuum 2d $U(N)$ gauge theories. https://doi.org/10.1103/physrevd.100.054502

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