Institut de recherche en mathematique et physique (IRMP)

Center for Cosmology, Particle Physics and Phenomenology (CP3)

Secteur des sciences et technologies
Invited seminars

Shedding light on new physics with Effective Field Theories

by Dr. Ilaria Brivio (NBI)

Wednesday, 7 February 2018 from to (Europe/Brussels)
at Cyclotron ( 1-3rd floor-E.349 - Seminar room (E.349) )
Description
Effective Field Theories (EFTs) are a powerful tool for investigating the presence of new physics beyond the Standard Model. We will first consider the Standard Model Effective Field Theory and discuss, in a "bottom-up" approach, how its parameters can be constrained with global fit analyses minimizing assumptions on the UV physics. As a case study I will present the results of a fit to electroweak data. The latter exhibits instructive features, among which the presence of two unconstrained combinations of Wilson coefficients whose origin can be understood in terms of a reparameterization invariance. 
The second part of the talk will follow a "top-down" perspective:  EFT techniques will be employed to take an alternative approach to the hierarchy problem, in which the Higgs mass is not stabilized around the TeV scale, but rather determined by radiative corrections at higher energies. In particular I will discuss the possibility that the Higgs potential is radiatively generated within a type-I seesaw model for neutrino masses.