Date: **November 15th 2017**

Speaker:** Eleonora Villa (SISSA)**

Title: **Theoretical systematics in galaxy clustering in LCDM and beyond**

**Abstract**

We study the impact of neglecting lensing magnification in galaxy clustering analyses for future galaxy surveys, considering the ΛCDM model and two extensions: massive neutrinos and modifications of General Relativity. Our study focuses on the biases on the constraints and on the estimation of the cosmological parameters. Our results show that the information present in the lensing contribution does improve the constraints on the modified gravity parameters whereas the lensing constraining power is negligible on the ΛCDM parameters. On the other hand the estimation is biased for all the parameters if lensing is not taken into account.

This effect is particularly significant for the modified gravity parameters. Our findings show the importance of including lensing in galaxy clustering analyses for testing General Relativity.