# 28th Texas Symposium on Relativistic Astrophysics

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
Talk

### 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

 Ballardini_ConstraintsOnInducedGravityDarkEnergyModels_Texas28.pdf InducedGravity_proc.pdf