2018/05/31 by Nicola Bartolo, Domenico Matteo Bianco, Raul Jimenez +2
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Dark energy #Einstein #Extra dimensions #Gravitation #Kinetic term #Moduli #Noncommutative and Quantum Gravity Theories #Planck #Term (time) #astro-ph.CO #hep-th
paper · pdf · doi:10.1088/1475-7516/2018/10/017
published as JCAP10(2018)017 · matches version published in JCAP; no major changes, conclusions unchanged
openalex created_date 2018/05/17 · arxiv created 2018/10/05 · openalex publication_date 2018/10/11 · arxiv updated 2018/11/14 · openalex updated_date 2026/08/05
We compute in detail how deviations from Einstein gravity at the inflation energy scale could appear as non-Gaussian features in the sky. To illustrate this we use multi-field α-attractor models in the framework of supergravity to realise inflation. We find no obvious obstacle for having choices of model's parameters that generate non-Gaussian features of the equilateral and local type at the 𝒪(1) level in the f NL non-Gaussianity parameter, thus being potentially detectable in future cosmological surveys. This non-Gaussianity has its origin in either the non-canonical kinetic term (which, in turn, is an immediate consequence of assuming an hyperbolic geometry of the moduli space), the interactions of the fields in the potential or the α-parameter, or a combination of these three. This opens up the exciting possibility of constraining the law of gravity at energy scales close to the Planck one.