Orateur
Description
Dark Gravity is a natural extension of General Relativity in the presence of a flat, non-dynamical background. We present an upgraded version of the theory in which the transition from the matter-dominated expansion law, a(t)∝t2/3, to the late-time accelerated regime, a(t)∝t2, occurs progressively rather than abruptly.
Compared with the version presented at the MG17 conference, the new model provides a significantly improved description of the main cosmological observations, including Type Ia supernovae, baryon acoustic oscillations (BAO), the cosmic microwave background (CMB), age estimates of the oldest stars, and direct measurements of the Hubble constant. The upgraded model introduces three free parameters—H0 and two transition redshifts—instead of the single transition redshift of the previous version.
After briefly reviewing the theoretical foundations of Dark Gravity and the original mechanism responsible for cosmic acceleration, we introduce the new transition scenario and discuss its observational performance.