Impact on the power spectrum of Screening in Modified Gravity Scenarios

Understand

We study the effects of screened modified gravity of the $f(R)$, dilaton and symmetron types on structure formation, from the quasi-linear to the non-linear regime, using semi-analytical methods.

• For such models, where the range of the new scalar field is typically within the Mpc range and below in the cosmological context, non-linear techniques are required to understand the deviations of the power spectrum of the matter density contrast compared to the $\Lambda$-CDM template.
• This is nowadays commonly tackled using extensive N-body simulations.
• Here we present new results combining exact perturbation theory at the one loop level (and a partial resummation of the perturbative series) with a halo model.