Constraints on two Higgs doublet models from domain walls

TL;DR

This paper identifies a universal constraint on two Higgs doublet models arising from stable vortex-domain wall systems, independent of fermion coupling details, with numerical solutions provided for cosmological implications.

Contribution

It introduces a new universal constraint on two Higgs doublet models based on topological defect stability, supported by numerical solutions of the field configurations.

Findings

Constraint depends on two parameter combinations

Stable vortex-domain wall systems are possible

Numerical solutions enable cosmological studies

Abstract

We show that there is a constraint on the parameter space of two Higgs doublet models that comes from the existence of the stable vortex-domain wall systems. The constraint is quite universal in the sense that it depends on only two combinations of Lagrangian parameters and does not depend on how fermions couple to two Higgs fields. Numerical solutions of field configurations of domain wall-vortex system are obtained, which provide a basis for further quantitative study of cosmology which involve such topological objects.