Speaker: Matteo Piani (COSTAR/CENTRA)
Title: Higgs-dilaton inflation in Einstein-Cartan gravity
Abstract:
Gravity can appear in different incarnations, from the commonly used metric formulation to the Palatini, teleparallel and Einstein-Cartan ones. Despite the difference in the choice of the fundamental degrees of freedom, all these formulations are equivalent in pure gravity scenarios, leading to the same equations of motion, therefore being devoided of any observational consequence. However, this equivalence is broken in the presence of a non-minimal coupling to matter, such as the Standard Model Higgs. Such coupling opens the possibility for the Higgs field to be responsible for the inflationary phase in the early universe. In this talk, I will discuss the phenomenology of Higgs-Inflation in the context of Einstein-Cartan gravity, together with its scale-invariant version, the so-called Higgs-dilaton model. In particular, I will show how the Einstein-Cartan formulation can endow a rich phenomenology, due to the unavoidable presence of extra gravitational operators, and interactions with fermionic matter. In a second part, I will discuss how this scenario can accommodate the formation of scalar compact objects in the early universe and the possible emission of gravitational waves.
Room: Sala de Reuniões e Seminários (2-8.3) (2nd Floor of Physics Building)