Landscape of Modular Symmetric Flavor Models

TL;DR

This paper explores how moduli stabilization in string theory influences flavor models, revealing that certain fixed points and CP-breaking vacua are statistically favored or disfavored, impacting flavor symmetry structures.

Contribution

It systematically analyzes moduli stabilization probabilities and their implications for modular flavor symmetries, highlighting favored fixed points and CP-breaking vacua in the string landscape.

Findings

Distribution of complex structure modulus $ au$ clusters at $ ext{Z}_3$ fixed points.

CP-breaking vacua are statistically disfavored in the landscape.

Values ${ m Re} au= ext{±}1/4$ are most favorable for CP phases.

Abstract

We study the moduli stabilization from the viewpoint of modular flavor symmetries. We systematically analyze stabilized moduli values in possible configurations of flux compactifications, investigating probabilities of moduli values and showing which moduli values are favorable from our moduli stabilization. Then, we examine their implications on modular symmetric flavor models. It is found that distributions of complex structure modulus $\tau$ determining the flavor structure are clustered at a fixed point with the residual $\mathbb{Z}_3$ symmetry in the $SL(2,\mathbb{Z})$ fundamental region. Also, they are clustered at other specific points such as intersecting points between $|\tau|^2=k/2$ and ${\rm Re}\,\tau=0,\pm 1/4, \pm1/2$, although their probabilities are less than the $\mathbb{Z}_3$ fixed point. In general, CP-breaking vacua in the complex structure modulus are statistically disfavored in the string landscape. Among CP-breaking vacua, the values ${\rm Re}\,\tau=\pm 1/4$ are most favorable in particular when the axio-dilaton $S$ is stabilized at ${\rm Re}\,S=\pm 1/4$. That shows a strong correlation between CP phases originated from string moduli.