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arXiv · 2512.20889

Explicit rephasing transformation of four-generation mixing matrix and formulae for CP phases

Masaki J. S. Yang
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Abstract

In this letter, we present an explicit rephasing transformation that maps a general $4\times4$ flavor mixing matrix to the standard parametrization of four-generation models. By combining rephasing-covariant minors and the determinant systematically, we derive expressions for all three Dirac-type CP phases, three Majorana phases, and four unphysical phases by arguments of matrix elements. The resulting formulae smoothly reduce to the three-generation results in the limit where the fourth generation decouples.

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Masaki J. S. Yang. 2025-12-24. Explicit rephasing transformation of four-generation mixing matrix and formulae for CP phases. https://arxiv.org/abs/2512.20889

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