Dark matter casts light on the early Universe

Abstract

We show how knowledge of the cold dark matter (CDM) density can be used, in conjunction with measurements of the parameters of a scenario for beyond the Standard Model (BSM) physics, to provide information about the evolution of the Universe before Big Bang Nucleosynthesis (BBN). As examples of non-standard evolution, we consider models with a scalar field that may decay into BSM particles, and quintessence models. We illustrate our calculations using various supersymmetric models as representatives of classes of BSM scenarios in which the CDM density is either larger or smaller than the observed density when the early Universe is assumed to be radiation-dominated. In the case of a decaying scalar field, we show how the CDM density can constrain the initial scalar density and the reheating temperature after it decays in BSM scenarios that would yield overdense dark matter in standard radiation-dominated cosmology, and how the decays of the scalar field into BSM particles can be constrained in scenarios that would otherwise yield underdense CDM. We also show how the early evolution of the quintessence field can be constrained in BSM scenarios.

The First Three Seconds: a Review of Possible Expansion Histories of the Early Universe

“…This makes it possible to circumvent the well-known ∼100 TeV upper limit on the mass of the DM, based on partial wave unitarity [414] (for related scenarios, see Refs. [415,416,417,341,418,295,278,419,227,420,421,422,39,261,282,423,284,424,288,265,425,426,289,301,300,427,428,429,430,431,432,433,302,434,435,436,437,438,439,290]; for alternative "freeze-in" production of DM in scenarios with a nonstandard expansion phase, see Refs. [440,441,425,442,443,426,289,…”

AlterBBN v2: A public code for calculating Big-Bang nucleosynthesis constraints in alternative cosmologies

“…In this scenario, a primordial scalar field is decaying, as described in [19]. Its density ρ φ follows the Boltzmann equation:…”

Higgsino dark matter in a non-standard history of the universe

“…If the dark matter freezes out in a non-standard history of the universe, the relic density of the dark matter would be much different. Such a scenario is well studied in the literature , and emphasized recently by [35][36][37][38][39][40][41][42][43][44][45][46].…”