The Cosmological Supersymmetron

TL;DR

The paper explores a supersymmetric dark energy model called the supersymmetron, analyzing its effects on cosmic acceleration and structure formation, and finds that observable signatures are possible but require an additional cosmological constant.

Contribution

It provides a detailed analysis of the supersymmetron's cosmological evolution, its impact on structure formation, and the necessity of an extra cosmological constant for consistency with observations.

Findings

Supersymmetron can cause observable modifications in structure formation.

A cosmological constant is needed for the model to match growth-rate observations.

Effects on large-scale structures persist at the non-linear level.

Abstract

Recently, a supersymmetric model of dark energy coupled to cold dark matter, the supersymmetron, has been proposed. In the absence of cold dark matter, the supersymmetron field converges to a supersymmetric minimum with a vanishing cosmological constant. When cold dark matter is present, the supersymmetron evolves to a matter dependent minimum where its energy density does not vanish and could lead to the present acceleration of the Universe. The supersymmetron generates a short ranged fifth force which evades gravitational tests. It could lead to observable signatures on structure formation due to a very strong coupling to dark matter. We investigate the cosmological evolution of the field, focusing on the linear perturbations and the spherical collapse and find that observable modifications in structure formation can indeed exist. Unfortunately, we find that when the growth-rate of perturbations is in agreement with observations, an additional cosmological constant is required to account for dark energy. In this case, effects on large scale structures are still present at the non-linear level which are investigated using the spherical collapse approach.