On the Higgs mass fine-tuning problem with multi-Higgs doublet models

Abstract

With no conclusive signal till date of the minimal supersymmetric and extra-dimensional models at the Large Hadron Collider (LHC), the issue of naturalness of the Higgs mass still calls for attention. One way to achieve that is to introduce additional bosonic degrees of freedom and rely on fine-tuning thereafter. That is, to arrange for a cancellation between various parameters so that the coefficient of the quadratically divergent term in the Higgs mass is vanishing or small to a manageable level. In this work, we explore the possibility of doing so using two- and three-Higgs doublet models. We consider different versions of the same and fold in various relevant constraints accordingly. The study reveals that the quadratically divergent mass term of the 125 GeV Higgs can be exactly canceled in most of the models considered here. However, the same does not hold for the nonstandard scalars owing to the applied constraints.