TY - JOUR
T1 - Testing the early universe with anisotropies of the gravitational wave background
AU - Dimastrogiovanni, Ema
AU - Fasiello, Matteo
AU - Malhotra, Ameek
AU - Meerburg, P. Daniel
AU - Orlando, Giorgio
N1 - Publisher Copyright:
© 2022 IOP Publishing Ltd and Sissa Medialab.
PY - 2022/2
Y1 - 2022/2
N2 - In this work we analyse in detail the possibility of using small and intermediate-scale gravitational wave anisotropies to constrain the inflationary particle content. First, we develop a phenomenological approach focusing on anisotropies generated by primordial tensor-tensor-scalar and purely gravitational non-Gaussianities. We highlight the quantities that play a key role in determining the detectability of the signal. To amplify the power of anisotropies as a probe of early universe physics, we consider cross-correlations with CMB temperature anisotropies. We assess the size of the signal from inflationary interactions against so-called induced anisotropies. In order to arrive at realistic estimates, we obtain the projected constraints on the non-linear primordial parameter F NL for several upcoming gravitational wave probes in the presence of the astrophysical gravitational wave background. We further illustrate our findings by considering a concrete inflationary realisation and use it to underscore a few subtleties in the phenomenological analysis.
AB - In this work we analyse in detail the possibility of using small and intermediate-scale gravitational wave anisotropies to constrain the inflationary particle content. First, we develop a phenomenological approach focusing on anisotropies generated by primordial tensor-tensor-scalar and purely gravitational non-Gaussianities. We highlight the quantities that play a key role in determining the detectability of the signal. To amplify the power of anisotropies as a probe of early universe physics, we consider cross-correlations with CMB temperature anisotropies. We assess the size of the signal from inflationary interactions against so-called induced anisotropies. In order to arrive at realistic estimates, we obtain the projected constraints on the non-linear primordial parameter F NL for several upcoming gravitational wave probes in the presence of the astrophysical gravitational wave background. We further illustrate our findings by considering a concrete inflationary realisation and use it to underscore a few subtleties in the phenomenological analysis.
KW - inflation
KW - physics of the early universe
KW - primordial gravitational waves (theory)
UR - http://www.scopus.com/inward/record.url?scp=85126294581&partnerID=8YFLogxK
U2 - 10.1088/1475-7516/2022/02/040
DO - 10.1088/1475-7516/2022/02/040
M3 - Article
AN - SCOPUS:85126294581
SN - 1475-7516
VL - 2022
JO - Journal of Cosmology and Astroparticle Physics
JF - Journal of Cosmology and Astroparticle Physics
IS - 2
M1 - 040
ER -