Constraints of Dark Energy at High Redshift

TL;DR

This paper investigates the limitations of current and future observational data in constraining dark energy at high redshift, highlighting the need for improved measurement accuracy to enhance constraints.

Contribution

It provides an analysis of why dark energy constraints weaken at high redshift and suggests that reducing observational errors is the most effective improvement method.

Findings

Current data poorly constrain dark energy beyond z=0.4

Future supernova data offer limited improvements

Reducing observational errors significantly improves high-redshift constraints

Abstract

Constrains of dark energy (DE) at high redshift from current and mock future observational data are obtained. It is found that present data give poor constraints of DE even beyond redshift z=0.4, and mock future 2298 type Ia supernove data only give a little improvement of the constraints. We analyze in detail why constraints of DE decrease rapidly with the increasing of redshift. Then we try to improve the constraints of DE at high redshift. It is shown that the most efficient way is to improve the error of observations.