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arXiv · 2008.00452

Small-scale Tests of Inflation

Laura Iacconi·Matteo Fasiello·Hooshyar Assadullahi·David Wands
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Abstract

We investigate small-scale signatures of the inflationary particle content. We consider the case of a light spin-2 particle sourcing primordial gravitational waves by employing an effective field theory description. Upon allowing time-dependent sound speeds for the helicity modes, this setup delivers a blue tensor spectrum detectable, for example, by upcoming laser interferometers. Our focus is on the tensor non-Gaussianities that ensue from this field configuration. After characterising the bispectrum amplitude and shape-function at CMB scales, we move on to smaller scales where anisotropies induced in the tensor power spectrum by long-short modes coupling become the key handle on (squeezed) primordial non-Gaussianities. We identify the parameter space generating percent level anisotropies at scales soon to be probed by SKA and LISA.

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Laura Iacconi, Matteo Fasiello, Hooshyar Assadullahi, David Wands. 2020-08-02. Small-scale Tests of Inflation. https://doi.org/10.1088/1475-7516/2020/12/005

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