Vacuum Structure in Two-Higgs Doublet Models

Event type
Event date
Venue
GAP room
Speaker
Pedro Ferreira (Centro de Física Teórica e Computacional)

AbstractThe Two-Higgs Doublet Model (2HDM) is one of the simples extensions of the Standard Model (SM) of particle physics. The introduction of a second Higgs doublet has interesting phenomenological consequences, namely a more complex vacuum structure than the SM's. In fact, in the 2HDM there are three possible types of vacua: the electroweak vacuum analogous to the SM one;  the charge breaking  vacuum, in which the electromagnetism symmetry is also broken, leaving the photon massive; and the CP breaking vacuum, for which the CP symmetry is spontanelously broken, alongside the electroweak symmetry. In this seminar we will demonstrate the impossibility of simultaneous coexistence of diferente types of mínima. We will also discuss the possible existence of tree-level metastable electroweak vacua, their importance in the light of the recente Higgs boson discovery at the LHC and the conditions which determine their existence and location of the global minimum of the model. We will finally discuss the generalization of these results for models with N Higgs doublets.