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arXiv · 1910.11553

$CP$ violation in modular invariant flavor models

Tatsuo Kobayashi·Yusuke Shimizu·Kenta Takagi·Morimitsu Tanimoto·Takuya H. Tatsuishi·Hikaru Uchida
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Abstract

We study the spontaneous $CP$ violation through the stabilization of the modulus $\tau$ in modular invariant flavor models. The $CP$-invaraiant potentential has the minimum only at ${\rm Re}[\tau] = 0$ or 1/2. From this prediction, we study $CP$ violation in modular invariant flavor models. The physical $CP$ phase is vanishing. The important point for the $CP$ conservation is the $T$ transformation in the modular symmetry. One needs the violation of $T$ symmetry to realize the spontaneous $CP$ violation.

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Tatsuo Kobayashi, Yusuke Shimizu, Kenta Takagi, Morimitsu Tanimoto, Takuya H. Tatsuishi, Hikaru Uchida. 2019-10-25. $CP$ violation in modular invariant flavor models. https://doi.org/10.1103/physrevd.101.055046

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