Hautes Energies

Higgs boson mass and stability of the EW vacuum

Europe/Paris
bat 25, salle Mondrian

bat 25, salle Mondrian

Description
After presenting the general framework for the stability analysis of the electroweak (EW) vacuum, I discuss the role of "new physics", maily in connection with the so called "metastability scenario". I show that, despite claims to the contrary, even in the event that new physics interactions only appear at the Planck scale, they may have a dramatic impact on the lifetime of the electroweak vacuum. In particular, it turns out that for the present experimental values of the Higgs mass, having or not a metastable EW vacuum with lifetime much larger than the age of the Universe, which amounts to the (by now) popular statement that we live in a metastable vacuum, strongly depends on the specific type of new physics. I also show that this analysis can be used as a test for different BSM (beyond standard model) theories. By Prof. Enzo Branchina.