Speaker
Description
In this work, we present a detailed computation of the standard and constraint effective potentials in 4-dimensional de Sitter spacetime. Second to the pathologies arising in the perturbation theory of "lighter-than-Hubble" scalars, the stochastic approach is commonly used in the literature to describe the dynamics of scalar degrees of freedom. However, some ambiguities appear in the set-up of this theory. Chiefly, the potential term in the stochastic equation of motion does not have a straightforward generalisation from the Minkowski case, as in curved geometries its definition becomes thermodynamic ensemble-dependent.
Starting from Euclidean path integral methods, we obtain novel, closed-form, analytical expressions for both potentials and examine whether either one is infrared (IR) and ultraviolet (UV) safe at one-loop in the asymptotically light limit, $\frac{m^2}{H^2} \rightarrow 0$. This work warrants the study of the dynamics, vacuum structure and stability of light cosmological spectators in a well-defined mathematical set-up.
