Mild quasilocal non-Gaussianity as a signature of modified gravity during inflation.

Phys Rev Lett

ICREA & ICC, University of Barcelona, Marti i Franques 1, Barcelona 08028, Spain and Institute of Theoretical Astrophysics, University of Oslo, 0315 Oslo, Norway.

Published: October 2014

We show that modifications of Einstein gravity during inflation could leave potentially measurable imprints on cosmological observables in the form of non-Gaussian perturbations. This is due to the fact that these modifications appear in the form of an extra field that could have nontrivial interactions with the inflaton. We show it explicitly for the case R+αR(2), where nearly scale-invariant non-Gaussianity at the level of f(NL) ≈ - (1 to 30) can be obtained, in a quasilocal configuration.

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http://dx.doi.org/10.1103/PhysRevLett.113.161303DOI Listing

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