Gravitational wave anisotropies as a probe of the inflationary particle content @LISAcommunity

Uploaded July 2022 | Updated September 2026, 2 hours ago

Stochastic gravitational wave backgrounds (SGWB) can be generated by a variety of processes in the early universe, most notably inflation. These backgrounds are characterised in terms of their spectral shape, polarization, (non-)Gaussianity and anisotropies. In this talk I will show how the anisotropies of the inflationary SGWB could be used to constrain primordial ultra-squeezed non-Gaussianity in the tensor sector and potentially probe the inflationary particle content. I will present projected constraints on the corresponding non linearity parameter FNL for several upcoming GW detectors including LISA and also highlight how the angular dependence of the primordial bispectrum affects these constraints. The angular dependence may be a signature of additional spinning fields present during inflation. This talk will be based on arxiv:2012.03498 and 2109.03077.

Author and Presenter: Ameek Malhotra

Gravitational wave anisotropies as a probe of the inflationary particle content

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