Stability of the EW vacuum, Higgs boson, and new physics

The possibility that the Standard Model (SM) is valid up to the Planck scale $M_P$, i.e. that new physics occurs only around $M_P$, is nowadays largely explored. For a metastable EW vacuum, we show that new physics interactions can have a great impact on its lifetime, and, differently from previous analyses, they cannot be neglected. Therefore, contrary to usual believes, the stability phase diagram of the SM depends on new physics. This has far reaching consequences. Beyond SM theories can be tested against their prediction for the stability of the EW vacuum. Moreover, despite of some recent claims, higher precision measurements of the top and Higgs masses cannot provide any definite answer on the SM stability properties. Finally, doubts on Higgs inflation scenarios, all based on results obtained neglecting new physics interactions, are also cast.