Possible Signatures of Inflationary Particle Content: Spin-2 Fields

Matteo Biagetti; Emanuela Dimastrogiovanni; Matteo Fasiello

doi:10.1088/1475-7516/2017/10/038

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arXiv · 1708.01587

Possible Signatures of Inflationary Particle Content: Spin-2 Fields

Matteo Biagetti·Emanuela Dimastrogiovanni·Matteo Fasiello

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Abstract

We study the imprints of a massive spin-2 field on inflationary observables, and in particular on the breaking of consistency relations. In this setup, the minimal inflationary field content interacts with the massive spin-2 field through dRGT interactions, thus guaranteeing the absence of Boulware-Deser ghostly degrees of freedom. The unitarity requirement on spinning particles, known as Higuchi bound, plays a crucial role for the size of the observable signal.

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Matteo Biagetti, Emanuela Dimastrogiovanni, Matteo Fasiello. 2017-08-04. Possible Signatures of Inflationary Particle Content: Spin-2 Fields. https://doi.org/10.1088/1475-7516%2F2017%2F10%2F038

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