Testing the Early Universe with Anisotropies of the Gravitational Wave Background

Understand

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.