Probing the early universe with future GW observatories

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Maity, Suvashis, Haque, Md Riajul
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912302018592768
author Maity, Suvashis
Haque, Md Riajul
author_facet Maity, Suvashis
Haque, Md Riajul
contents One of the fundamental characteristics of slow roll inflation is its generation of tensor perturbations, which manifest as stochastic gravitational waves (GWs). Slow roll inflation results in a nearly scale-invariant GW spectrum that maintains its scale invariance as it transitions into the radiation-dominated era. However, introducing an intermediate reheating phase can modify the spectral tilt, depending on the equation of state governing that particular epoch. These GWs, especially on smaller scales, are anticipated to be observable by forthcoming GW detectors. In this study, we initially delineate the parameter space encompassing the inflationary energy scale, reheating temperature, and equation of state in a model-independent manner, focusing on the spectra detectable by GW detectors such as LISA, ET, DECIGO, and BBO. We also examine the implications for the $α$-attractor model of inflation and explore the observational constraints on $n_s-r$ prediction in the light of GW detection. Then, we point out the probable ranges for various non-gravitational and gravitational coupling between the inflaton and Standard Model particles considering the perturbative reheating. If one assumes PBHs were formed during the early reheating era, such detection of GW signal also sheds light on the probing PBH parameters. Note that for the case of PBH domination, we also consider the contribution of the induced GWs due to the density fluctuation in PBH distribution, which helps to decode the phase of early PBH domination. Finally, to test the production of other cosmological relics through future GW missions, we consider dark matter produced via gravitational interaction in the early universe.
format Preprint
id arxiv_https___arxiv_org_abs_2407_18246
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Probing the early universe with future GW observatories
Maity, Suvashis
Haque, Md Riajul
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
One of the fundamental characteristics of slow roll inflation is its generation of tensor perturbations, which manifest as stochastic gravitational waves (GWs). Slow roll inflation results in a nearly scale-invariant GW spectrum that maintains its scale invariance as it transitions into the radiation-dominated era. However, introducing an intermediate reheating phase can modify the spectral tilt, depending on the equation of state governing that particular epoch. These GWs, especially on smaller scales, are anticipated to be observable by forthcoming GW detectors. In this study, we initially delineate the parameter space encompassing the inflationary energy scale, reheating temperature, and equation of state in a model-independent manner, focusing on the spectra detectable by GW detectors such as LISA, ET, DECIGO, and BBO. We also examine the implications for the $α$-attractor model of inflation and explore the observational constraints on $n_s-r$ prediction in the light of GW detection. Then, we point out the probable ranges for various non-gravitational and gravitational coupling between the inflaton and Standard Model particles considering the perturbative reheating. If one assumes PBHs were formed during the early reheating era, such detection of GW signal also sheds light on the probing PBH parameters. Note that for the case of PBH domination, we also consider the contribution of the induced GWs due to the density fluctuation in PBH distribution, which helps to decode the phase of early PBH domination. Finally, to test the production of other cosmological relics through future GW missions, we consider dark matter produced via gravitational interaction in the early universe.
title Probing the early universe with future GW observatories
topic Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
url https://arxiv.org/abs/2407.18246