Direct dark matter searches - Test of the Big Bounce Cosmology

TL;DR

This paper proposes that dark matter particle properties could serve as indicators of a Big Bounce cosmology, with unique production mechanisms and relations differing from standard cosmology, providing testable signatures in direct detection experiments.

Contribution

It introduces a novel cosmological model where dark matter production during a bounce phase predicts distinctive relations between mass and cross section, offering a new way to test early universe scenarios.

Findings

Dark matter production during a bounce affects relic abundance.

A characteristic relation between dark matter mass and cross section is predicted.

Direct detection could confirm the bounce universe scenario.

Abstract

We consider the possibility of using dark matter particle's mass and its interaction cross section as a smoking gun signal of the existence of a Big Bounce at the early stage in the evolution of our currently observed universe. A study of dark matter production in the pre-bounce contraction and the post bounce expansion epochs of this universe reveals a new venue for achieving the observed relic abundance of our present universe. Specifically, it predicts a characteristic relation governing a dark matter mass and interaction cross section and a factor of $1/2$ in thermally averaged cross section, as compared to the non-thermal production in standard cosmology, is needed for creating enough dark matter particle to satisfy the currently observed relic abundance because dark matter is being created during the pre-bounce contraction, in addition to the post-bounce expansion. As the production rate is lower than the Hubble expansion rate information of the bounce universe evolution is preserved. Therefore once the value of dark matter mass and interaction cross section are obtained by direct detection in laboratories, this alternative route becomes a signature prediction of the bounce universe scenario. This leads us to consider a scalar dark matter candidate, which if it is light, has important implications on dark matter searches.