# Quark mixing in an $S_3$ symmetric model with two Higgs doublets

## TL;DR

This paper presents an $S_3$ symmetric two-Higgs-doublet model that links small first-generation quark masses to a near block-diagonal CKM matrix, predicting Higgs properties and flavor-changing neutral currents.

## Contribution

It introduces a novel $S_3$ symmetric 2HDM framework that naturally explains quark mass hierarchies and CKM structure, with precise predictions for $ aneta$ and FCNC behavior.

## Key findings

- Emergence of an SM-like Higgs from the model
- Determination of $ aneta$ from quark mass constraints
- Predictive FCNC structure

## Abstract

We construct a model where the smallness of the masses of first quark generations implies the near block diagonal nature of the CKM matrix and vice-versa. For this set-up, we rely on a 2HDM structure with an $S_3$ symmetry. We show that an SM-like Higgs emerges naturally from such a construction. Moreover, the ratio of two VEVs, $\tan\beta$ can be precisely determined from the requirement of the near masslessness of the up- and down-quarks. The FCNC structure that arises from our model is also very predictive.