13-18 December 2015
International Conference Centre Geneva
Europe/Zurich timezone

Constraints on induced gravity dark energy models

15 Dec 2015, 14:53
26m
Level 2, Room 14 (International Conference Centre Geneva)

Level 2, Room 14

International Conference Centre Geneva

17 Rue de Varembé, 1211 Geneva

Speaker

Mario Ballardini (University of Bologna)

Description

We study the predictions for structure formation in an induced gravity dark energy model with a quartic potential. By developing a dedicated Einstein-Boltzmann code, we study self-consistently the dynamics of homogeneous cosmology and of linear perturbations without using any parametrization, accurately recovering the quasi-static analytic approximation in the matter dominated era. We use CMB anisotropies data and a compilation of BAO data to constrain the coupling $\gamma$ to the Ricci curvature and the other cosmological parameters. By connecting the gravitational constant in the Einstein equation to the one measured in a Cavendish-like experiment, we find $\gamma < 0.0012$ at 95 % confidence level with Planck 2013 and BAO data, and present the updated Planck 2015 constraint. Because of a degeneracy between $\gamma$ and the Hubble constant $H_0$, we show how larger values for $\gamma$ are allowed, but not preferred at a significant statistical level, when local measurements of $H_0$ are combined in the analysis with Planck data. We also extend the analysis and constraints to a simple monomial potential with a positive exponent.

Primary author

Mario Ballardini (University of Bologna)

Presentation Materials