Title: Clustering measurements in the final eBOSS quasar sample and their cosmological implications

Abstract:In this talk I present the clustering analysis of the final extended Baryon Oscillation Spectroscopic Survey (eBOSS) quasar sample at redshift 0.8<z<2.2, which bridges the redshift gap between the eBOSS LRG and Lyman-alpha measurements. Mapping the evolution of the expansion and growth of structure histories of our Universe provides us with a crucial test of the standard LCDM cosmological scenario. Our analysis includes a detailed modelling of the impact of the non-linear evolution of density fluctuations, bias, and redshift-space distortions on the two-point correlation function. Using numerical simulations designed to reproduce the uniqueness of the quasar sample, we perform extensive validation tests to characterise potential systematic errors induced by theoretical and observational effects. The constraints obtained from anisotropic clustering measurements can be used to test models of gravity on large-scales. However, these tests require the validation of our analysis techniques in modified gravity scenarios. I present an example of such tests, based on large numerical simulations of standard and modified gravity models to measure galaxy clustering in redshift space.