Testing coupled dark energy with next-generation large-scale observations

TL;DR

This paper evaluates how upcoming large-scale astronomical observations can significantly tighten constraints on models where dark energy interacts with dark matter, potentially revealing new physics beyond current limits.

Contribution

It provides forecasts for future observational constraints on coupled dark energy models, demonstrating potential improvements over existing bounds by two orders of magnitude.

Findings

Future observations can improve coupling constraints by 100x.

Next-generation data will complement solar-system bounds.

Combined probes enhance sensitivity to dark energy-dark matter interactions.

Abstract

Coupling dark energy to dark matter provides one of the simplest way to effectively modify gravity at large scales without strong constraints from local (i.e. solar system) observations. Models of coupled dark energy have been studied several times in the past and are already significantly constrained by cosmic microwave background experiments. In this paper we estimate the constraints that future large-scale observations will be able to put on the coupling and in general on all the parameters of the model. We combine cosmic microwave background, tomographic weak lensing, redshift distortions and power spectrum probes. We show that next-generation observations can improve the current constraint on the coupling to dark matter by two orders of magnitude; this constraint is complementary to the current solar-system bounds on a coupling to baryons.