Phenomenology of a rolling axion in the early and late universe

by Marco Peloso (INFN Padova)

HS3 (Physikdepartment)




We will discuss several consequence of the gauge field production from an axion field that is evolving either during the primordial or the current accelerated stage of expansion of the universe. In the first case, the produced gauge field can source non-Gaussian scalar perturbations, the seeds of Primordial Black-Holes (PBH), and Gravitational Waves (GW) at CMB and at interferometer scales. Motivated by this, we will also discuss strategies for the characterization of the Stochastic GW background of cosmological origin. In the late universe application, we will discuss the possibility that the gauge field production provides an additional source of friction for the motion of the pseudo-scalar, so that the pseudo-scalar can behave as dark energy also in potentials that are too steep to lead to accelerated expansion in absence of this production.

Your browser is out of date!

Update your browser to view this website correctly. Update my browser now