WIMP Dark Matter Inflation with Observable Gravity Waves

TL;DR

This paper proposes a inflation model where a TeV-scale SM singlet scalar acts as both the inflaton and a WIMP dark matter candidate, predicting observable gravity waves within current experimental bounds.

Contribution

It introduces a $ ext{lambda} \, ext{phi}^4$ inflation model with a TeV-scale scalar that unifies inflation and dark matter, with testable gravity wave predictions.

Findings

WIMP relic abundance matches observations

Spectral index $n_s$ within WMAP bounds

Tensor-to-scalar ratio between 0.003 and 0.007

Abstract

We present a successful inflation model based on $\lambda \phi^4$ potential in which a Standard Model (SM) singlet inflaton $\phi$, with mass of around a TeV or less, also plays the role of a weakly interacting scalar dark matter particle (WIMP). The WIMP relic abundance generated after inflation is in accord with the current observations. The spectral index $n_s$ lies within the WMAP 1-$\sigma$ bounds, while the Planck satellite may observe the tensor-to-scalar ratio, a canonical measure of gravity waves, which we estimate lies between 0.003 and 0.007.An unbroken $Z_2$ parity ensures that the scalar WIMP is absolutely stable.