A natural mechanism for a SM-like Higgs boson in the 2HDM without decoupling (2205.07578v2)

Abstract: The properties of the Higgs boson discovered at the Large Hadron Collider are very well described by the Standard Model (SM). Thus, any theory that invokes an extended Higgs sector must explain why the neutral scalar observed at the LHC so closely resembles the SM Higgs boson. In this talk, I review the Higgs alignment limit, in which one neutral scalar state of the Higgs sector is SM-like. An approximate Higgs alignment can be achieved "naturally" either via decoupling or via an approximate symmetry. Using the two-Higgs doublet model as a prototype for an extended Higgs sector, I examine the symmetries of the scalar potential and their soft breakings that may be responsible for the SM-like properties of the observed Higgs boson, and I demonstrate how to extend such (softly-broken) symmetries to the Yukawa sector of the model.