Gravitational wave signatures of no-scale Supergravity in NANOGrav and beyond
High Energy Physics - Theory2024-02-08v5Cosmology and Nongalactic AstrophysicsGeneral Relativity and Quantum CosmologyHigh Energy Physics - Phenomenology
In this Letter, we derive for the first time a characteristic three-peaked GW signal within the framework of no-scale Supergravity, being the low-energy limit of Superstring theory. We concentrate on the primordial gravitational wave (GW) spectrum induced due to second-order gravitational interactions by inflationary curvature perturbations as well as by isocurvature energy density perturbations of primordial black holes (PBHs) both amplified due to the presence of an early matter-dominated era (eMD) era before Big Bang Nucleosythesis (BBN). In particular, we work with inflection-point inflationary potentials naturally-realised within Wess-Zumino type no-scale Supergravity and giving rise to the formation of microscopic PBHs triggering an eMD era and evaporating before BBN. Remarkably, we obtain an abundant production of gravitational waves at the frequency ranges of nHz, Hz and kHz and in strong agreement with Pulsar Time Array (PTA) GW data. Interestingly enough, a simultaneous detection of all three nHz, Hz and kHz GW peaks can constitute a potential observational signature for no-scale Supergravity.
@article{arxiv.2307.08601,
title = {Gravitational wave signatures of no-scale Supergravity in NANOGrav and beyond},
author = {Spyros Basilakos and Dimitri V. Nanopoulos and Theodoros Papanikolaou and Emmanuel N. Saridakis and Charalampos Tzerefos},
journal= {arXiv preprint arXiv:2307.08601},
year = {2024}
}