Work

Constraints on the Pre-Big Bang scenario from a cosmological interpretation of the NANOGrav data

Year: 2025

Type: article

Abstract: 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 background of primordial gravitons, produced in the context of the string cosmology pre-big bang scenario. We show that such interpretation cannot be reconciled with a phenomenologically viable minimal version of such scenario, while it can be allowed if one considers an equally viable but generalised, non-minimal version of pre-big bang evolution. Maintaining the S-duality symmetry throughout the high-curvature string phase is possible although somewhat disfavoured. The implications of this non-minimal scenario for the power spectrum of curvature perturbations are also briefly discussed.

Source: Journal of Cosmology and Astroparticle Physics

DOI: 10.1088/1475-7516/2025/02/039

Authors: P. Conzinu, G. Fanizza, M. Gasperini, E. Pavone, L. Tedesco, G. Veneziano

Institution: Collège de France

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,290