Speaker
Massimiliano Rinaldi
(University of Trento)
Description
Recently Kallosh, Linde, and collaborators have provided a unified description of single-field inflation in terms of just one parameter α. These so-called α-attractors predict a spectral index n_s and a tensor-to-scalar ratio r, which are fully compatible with the latest Planck data. The only common feature of all α-attractors is a non-canonical kinetic term with a pole, and a potential analytic around the pole.
Starting from the same Einstein frame with a non-canonical scalar kinetic energy, we explore the case of non-analytic potentials and find that they all correspond to quasi-scale invariant gravitational models in the Jordan frame, characterised by a universal relation between r and ns that fits the observational data but is clearly distinct from the one of the α- attractors.
Since the breaking of the exact classical scale-invariance in the Jordan frame can be attributed to one-loop corrections, we desume that non-analytic potentials in the non-canonical Einstein frame are physically equivalent to an entire class of models in the Jordan frame, with scale-invariance softly broken by one-loop quantum corrections.
| Collaboration | L. Vanzo; S. Zerbini; G. Cognola; G. Venturi |
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Primary author
Massimiliano Rinaldi
(University of Trento)
