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arXiv · 1612.05770

$θ$ and the $η^\prime$ in Large $N$ Supersymmetric QCD

Michael Dine·Patrick Draper·Laurel Stephenson-Haskins·Di Xu
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Abstract

We study the large $N$ $θ$ dependence and the $η^\prime$ potential in supersymmetric QCD with small soft SUSY-breaking terms. Known exact results in SUSY QCD are found to reflect a variety of expectations from large $N$ perturbation theory, including the presence of branches and the behavior of theories with matter (both with $N_f \ll N$ and $N_f \sim N$). However, there are also striking departures from ordinary QCD and the conventional large $N$ description: instanton effects, when under control, are not exponentially suppressed at large $N$, and branched structure in supersymmetric QCD is always associated with approximate discrete symmetries. We suggest that these differences motivate further study of large $N$ QCD on the lattice.

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Michael Dine, Patrick Draper, Laurel Stephenson-Haskins, Di Xu. 2017-05-21. $θ$ and the $η^\prime$ in Large $N$ Supersymmetric QCD. https://doi.org/10.1007/jhep05(2017)122

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