The general Two-Higgs Doublet Model in a gauge-invariant form

TL;DR

This paper develops a gauge-invariant formulation of the general Two-Higgs Doublet Model, enabling a clearer understanding of its physical properties and interactions without gauge ambiguities.

Contribution

It extends previous work by expressing all masses and couplings in the THDM in a gauge-invariant manner, simplifying analysis of the model's phenomenology.

Findings

All masses and couplings are expressed gauge-invariantly.

The framework clarifies stability and symmetry breaking analysis.

It facilitates more physical interpretations of the model.

Abstract

In the general Two-Higgs Doublet Model it has been shown that the Higgs potential can be expressed in terms of gauge-independent quantities. In particular, stability, electroweak symmetry breaking, and CP symmetry can be understood in a concise way, avoiding unphysical gauge degrees of freedom. We complete this program and show how all the masses, the trilinear and quartic scalar interactions, the gauge-boson-Higgs interactions, as well as the Yukawa couplings in the general THDM can be expressed in a gauge-invariant way.