4 papers
Freeze-out and spectral running of primordial gravitational waves in viscous cosmology
Giuseppe Fanizza, Eliseo Pavone, Luigi Tedesco
We investigate the impact of shear viscosity on the propagation of primordial gravitational waves (pGW) after inflation. Without assuming a specific inflationary scenario we focus…
Viscosity in Isotropic Cosmological Backgrounds in General Relativity and Starobinsky Gravity
Eliseo Pavone, Luigi Tedesco
We present a general analysis of the role of shear viscosity in cosmological backgrounds, focusing on isotropic space-time in both Einstein and gravity. By computing the div…
From the string vacuum to FLRW or de Sitter via corrections
P. Conzinu, G. Fanizza, M. Gasperini +3
We first make more precise a recent "Hamiltonian" reformulation of the Hohm-Zwiebach approach to the tree-level, -invariant string cosmology equations at all orders in the…
Constraints on the Pre-Big Bang scenario from a cosmological interpretation of the NANOGrav data
P. Conzinu, G. Fanizza, M. Gasperini +3
We discuss a recently proposed fit of the 15-year data set obtained from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) in terms of a relic stochastic…