7–11 Jul 2025
Northeastern University
US/Eastern timezone

Cosmic superstrings in large volume compactifications: PTAs, LISA and time-varying tension

8 Jul 2025, 16:06
17m
ISEC (Northeastern University)

ISEC

Northeastern University

Interdisciplinary Science & Engineering Complex (ISEC) 805 Columbus Ave, Boston, MA 02120

Speaker

Filippo Revello

Description

The Stochastic Gravitational Wave Background (SGWB) from cosmic super- strings offers one of the few known possibilities to test String Theory within current experimental reach. However, in order to be compatible with the existing constraints, the tension of a cosmic superstring network is required to lie several orders of magnitude below the Planck scale. This is naturally realized in string compactifications where the volume of the extra dimensions is parametrically large (in string units). We estimate the GW spectrum arising from cosmic superstrings in such scenarios, providing analytical formulae as well as numerical results and a comparison to observation. Crucially, we do so within a fully-fledged string cosmology, taking into account various modified cosmological epochs (such as kination or early matter domination) induced by the presence of moduli and a time-dependent string tension.

Presentation materials