Confronting DGP braneworld gravity with cosmico observations after Planck data

Abstract

The normal branch of Dvali-Gabadadze-Porrati braneworld gravity with brane tension is confronted by the currently available cosmic observations from the geometrical and dynamical perspectives. On the geometrical side, the type Ia supernova as standard candle, the baryon acoustic oscillation as standard ruler and the cosmic microwave background measurement from the first released 15.5 months data were used to fix the background evolutions. On the dynamical side, the redshift space distortion data will be used to determine the evolution of the matter perturbation. Through a Markov chain Monte Carlo analysis, we found the dimensionless crossover scale Ωrc = 1/(4H20r2c) = 0.00183−0.00183+0.000338 in a spatially flat normal branch of Dvali-Gabadadze-Porrati braneworld. This result suggests that the crossover scale rc should be around 12H−10 which is consistent with the previous result rc > 3H−10 and greater. It also implies that the five-dimensional gravity effect is weak to be observed in H−10 scale.