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arXiv · 2402.12453

Non-Invertible Peccei-Quinn Symmetry and the Massless Quark Solution to the Strong CP Problem

Clay Cordova·Sungwoo Hong·Seth Koren
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Abstract

We consider theories of gauged quark flavor and identify non-invertible Peccei-Quinn symmetries arising from fractional instantons when the resulting gauge group has non-trivial global structure. Such symmetries exist solely because the Standard Model has the same numbers of generations as colors, $N_g = N_c$. This leads us to a massless down-type quark solution to the strong CP problem in an ultraviolet $SU(9)$ theory of quark color-flavor unification. We show how the CKM flavor structure and weak CP violation can be generated without upsetting our solution.

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Clay Cordova, Sungwoo Hong, Seth Koren. 2024-02-19. Non-Invertible Peccei-Quinn Symmetry and the Massless Quark Solution to the Strong CP Problem. https://arxiv.org/abs/2402.12453

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