Probing the interaction between dark energy and dark matter with future fast radio burst observations

TL;DR

Future large-scale FRB observations could significantly improve constraints on dark energy-dark matter interactions, surpassing current CMB data, and enable precise measurement of the coupling parameter in various IDE models.

Contribution

This study demonstrates the potential of future FRB data to tightly constrain the interaction parameter in dark energy-dark matter models, a significant advancement over current observational limits.

Findings

Approximately 10^5 FRBs can outperform current CMB constraints on the interaction parameter.

About 10^6 FRBs can reduce the error in the coupling parameter to below 0.10.

Jointly constraining FRB and cosmological parameters increases the uncertainty in the interaction parameter.

Abstract

Interacting dark energy (IDE) scenario assumes that there exists a direct interaction between dark energy and cold dark matter, but this interaction is hard to be tightly constrained by the current data. Fast radio bursts (FRBs) will be seen in large numbers by future radio telescopes, and thus they have potential to become a promising low-redshift cosmological probe. In this work, we investigate the capability of future FRBs of constraining the dimensionless coupling parameter $\beta$ in four phenomenological IDE models. If we fix the FRB properties, about $10^5$ FRB data can give constraints on $\beta$ tighter than the current cosmic microwave background data in the IDE models with the interaction proportional to the energy density of dark energy. In all the IDE models, about $10^6$ FRB data can achieve the absolute errors of $\beta$ to less than $0.10$, providing a way to precisely measure $\beta$ by only one cosmological probe. Jointly constraining the FRB properties and cosmological parameters would increase the constraint errors of $\beta$ by a factor of about 0.5-2.