Probing the cosmic acceleration from combinations of different data sets

TL;DR

This paper investigates how systematic uncertainties in various cosmological data sets affect the inferred evolution of dark energy, comparing two parametrizations to assess their robustness.

Contribution

It provides a detailed analysis of the impact of data systematics on dark energy evolution and compares two different parametrizations for robustness.

Findings

Data systematics influence dark energy evolution results.

Both parametrizations are affected by data systematics.

Dark energy behavior varies with different data sets and models.

Abstract

We examine in some detail the influence of the systematics in different data sets including type Ia supernova sample, baryon acoustic oscillation data and the cosmic microwave background information on the fitting results of the Chevallier-Polarski-Linder parametrization. We find that the systematics in the data sets does influence the fitting results and leads to different evolutional behavior of dark energy. To check the versatility of Chevallier-Polarski-Linder parametrization, we also perform the analysis on the Wetterich parametrization of dark energy. The results show that both the parametrization of dark energy and the systematics in data sets influence the evolutional behavior of dark energy.