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arXiv · 2408.12146

Three-zero texture of quark-mass matrices as a solution to the strong CP problem

Qiuyue Liang·Risshin Okabe·Tsutomu T. Yanagida
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Abstract

The strong charge-parity (CP) problem has been a long-standing problem in particle physics since 1976, illustrating the small CP-violation phase in quantum chromodynamics (QCD). The axion, based on the Peccei-Quinn mechanism, is the most popular solution to the problem. In this paper, we propose an alternative solution based on the three-zero texture of quark mass matrices without additional heavy quark states, which has been shown to fit data well. We show that the required three-zero texture is naturally constructed in a six-dimensional spacetime with a $\mathbf{T}^2/\mathbb{Z}_3$ orbifold compactification.

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Qiuyue Liang, Risshin Okabe, Tsutomu T. Yanagida. 2024-08-22. Three-zero texture of quark-mass matrices as a solution to the strong CP problem. https://arxiv.org/abs/2408.12146

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