Cosmological Constraints on the DGP braneworld model with Gamma-ray bursts

TL;DR

This study uses multiple cosmological observations, including Gamma-ray bursts and supernovae data, to place tighter constraints on the DGP braneworld model, favoring a flat universe and identifying the transition redshift.

Contribution

It provides the first comprehensive constraint on the DGP model using high-redshift Gamma-ray bursts combined with other cosmological data sets.

Findings

Best-fit matter density parameter Ω_M0 ≈ 0.235

Best-fit crossover scale parameter Ω_rc ≈ 0.138

Transition redshift z_T ≈ 0.67

Abstract

We investigate observational constraints on the Dvali, Gabadadze and Porrati (DGP) model with Gamma-ray bursts (GRBs) at high redshift obtained directly from the Union2 Type Ia supernovae data (SNe Ia) set. With the cosmology-independent GRBs, the Union2 set, as well as the cosmic microwave background (CMB) observations from the WMAP7 result, the baryon acoustic oscillation, the baryon mass fraction in clusters and the observed $H(z)$ data, we obtain that the best-fit values of the DGP model are ${\Omega_{M0}, \Omega_{rc}} =\{0.235_{-0.014}^{+0.015},0.138_{-0.048}^{+0.051}\}$, which favor a flat universe; and the transition redshift of the DGP model is $z_T=0.67_{-0.04}^{+0.03}$. These results lead to more stringent constraints than the previous results for the DGP model.