Minimal Scale Invariant Theory of Electroweak Symmetry Breaking

por Apostolos Pilaftsis (CERN & Manchester U.)

miércoles 1 jun. 2011 12:00 → 13:00 Europe/Madrid

Sala Seminarios (Dpto. de Física Teórica (UVEG))

Scaling symmetries may provide a calculable mechanism for solving the gauge hierarchy problem. In my talk, I will present a minimal and perturbative realization of this idea, by analyzing a Minimal Scale Invariant extension of the Standard Model (MSISM) by adding a complex singlet scalar field. I will review the Gildener--Weinberg approach to the radiative lifting of the flat directions that may occur in a scale-invariant Higgs potential and use it to determine the electroweak symmetry breaking in the MSISM. Then, I will discuss a number of representative scenarios, which include right-handed neutrinos and Dark Matter candidates, and determine their scalar boson mass spectra, compatible with electroweak precision data. In particular, I will analyze a Z_4 symmetric version of the MSISM with maximal spontaneous CP violation which can stay perturbative up to Planck-mass energy scales, without introducing an unnaturally large hierarchy in the scalar-potential couplings.