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 T2/Z3 orbifold compactification.

中文翻译：

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夸克质量矩阵的三零纹理作为强 CP 问题的解决方案


自 1976 年以来，强电荷奇偶性 （CP） 问题一直是粒子物理学中一个长期存在的问题，这说明了量子色动力学 （QCD） 中的小 CP 违规阶段。基于 Peccei-Quinn 机制的轴子是该问题最流行的解决方案。在本文中，我们提出了一种基于夸克质量矩阵的三零纹理的替代解决方案，没有额外的重夸克态，这已被证明可以很好地拟合数据。我们表明，所需的三零纹理是在 T2/Z3 球形压缩的六维时空中自然构建的。