Speaker
Description
We study a Symmetric Teleparallel Gravity with a Lagrangian of Logarithmic form. The full model leads to an accelerated Universe and for specific values of the free parameters the Hubble rate reduces to the well known DGP model, though the evolution of the gravitational potentials are different. We consider different branches of the Logarithmic model, among which sDGP and nDGP. The phenomenology of both the background and linear perturbations is discussed, including all the relevant effects on Cosmic Microwave Background radiation (CMB) angular power spectrum, lensing and matter power spectra. To this purpose, we modified the Einstein-Boltzmann code MGCAMB.
In some cases, it is possible to have a phenomenology such that the lensing auto-correlation power spectrum is enhanced and the matter power spectrum is suppressed for the same choice of parameters. These features are of interest in view of understanding the excess of lensing in CMB data and the $\sigma_8$ tension. In some cases it is possible to have a suppressed ISW tail which is a feature preferred by CMB data;
