Probing the BSM physics with CMB precision cosmology: an application to supersymmetry

TL;DR

This paper investigates how precision measurements of the CMB can test supersymmetry and other BSM theories by analyzing the impact of alternative cosmic histories on key observables, emphasizing the potential to complement laboratory searches.

Contribution

It quantifies the effects of non-standard cosmic histories on CMB observables within supersymmetry frameworks, highlighting the importance of early universe modeling for BSM physics testing.

Findings

Alternative cosmic histories significantly affect $n_s$ and $r$ predictions.

Supersymmetry breaking schemes influence the required reheating temperatures.

Unified early universe models improve CMB prediction accuracy.

Abstract

The cosmic history before the BBN is highly determined by the physics that operates beyond the Standard Model (BSM) of particle physics and it is poorly constrained observationally. Ongoing and future precision measurements of the CMB observables can provide us with significant information about the pre-BBN era and hence possibly test the cosmological predictions of different BSM scenarios. Supersymmetry is a particularly motivated BSM theory and it is often the case that different superymmetry breaking schemes require different cosmic histories with specific reheating temperatures or low entropy production in order to be cosmologically viable. In this paper we quantify the effects of the possible alternative cosmic histories on the $n_s$ and $r$ CMB observables assuming a generic non-thermal stage after cosmic inflation. We analyze TeV and especially multi-TeV supersymmetry breaking schemes assuming the neutralino and gravitino dark matter scenarios. We complement our analysis considering the Starobinsky $R^2$ inflation model to exemplify the improved CMB predictions that a unified description of the early universe cosmic evolution yields. Our analysis underlines the importance of the CMB precision measurements that can be viewed, to some extend, as complementary to the laboratory experimental searches for supersymmetry or other BSM theories.