Supersymmetric standard model inflation in the Planck era

TL;DR

This paper presents a supergravity-based inflation model within the Standard Model with right-handed neutrinos, achieving successful inflation without unitarity issues and linking neutrino mass scales to cosmological observations.

Contribution

It introduces a novel inflation scenario using the L-H_u direction in supergravity, avoiding unitarity problems and connecting neutrino mass scales with cosmological data.

Findings

Inflation driven by the L-H_u direction in supergravity is successful.

The model predicts a lower bound on right-handed neutrino mass scale $M_R \,\gtrsim\ 1$ TeV.

Future Planck data can discriminate this model and constrain $M_R$.

Abstract

We propose a cosmological inflationary scenario based on the supergravity-embedded Standard Model supplemented by the right-handed neutrinos. We show that with an appropriate Kahler potential the L-H_u direction gives rise to successful inflation that is similar to the recently proposed gravitationally coupled Higgs inflation model but is free from the unitarity problem. The mass scale $M_R$ of the right-handed neutrinos is subject to the seesaw relation and the present 2-$\sigma$ constraint from the WMAP7-BAO-H_0 data sets its lower bound $M_R\gtrsim$ 1 TeV. Generation of the baryon asymmetry is naturally implemented in this model. We expect within a few years new observational data from the Planck satellite clearly discriminates this model from other existing inflationary models arising from the same Lagrangian, and possibly yields stringent constraints on $M_R$.