Elucidating Dark Energy with Future 21 cm Observations at the Epoch of Reionization

TL;DR

This paper explores how future 21 cm observations during the epoch of reionization can significantly improve constraints on dark energy properties, especially its equation of state and evolution.

Contribution

It demonstrates the potential of upcoming 21 cm surveys combined with other cosmological data to tightly constrain dark energy models, including those with high-redshift variations.

Findings

Future 21 cm observations will significantly improve dark energy constraints.

Combining 21 cm data with CMB, BAO, SNe, and H0 measurements enhances parameter estimation.

High-redshift EoS variations are particularly well constrained by 21 cm surveys.

Abstract

We investigate how precisely we can determine the nature of dark energy such as the equation of state (EoS) and its time dependence by using future observations of 21 cm fluctuations at the epoch of reionization (6.8 <~ z <~ 10) such as Square Kilometre Array (SKA) and Omniscope in combination with those from cosmic microwave background, baryon acoustic oscillation, type Ia supernovae and direct measurement of the Hubble constant. We consider several parametrizations for the EoS and find that future 21 cm observations will be powerful in constraining models of dark energy, especially when its EoS varies at high redshifts.