His interests include different aspects of theoretical and observational cosmology: how did structure emerge in the Universe? What did seed the initial structure? How and when did galaxies and stars form? What is (dark) matter/energy (made of)? My activity has focused on the study of cosmological models and Large Scale Structure (LSS): to understand the emergence of structure as inferred from observations of how different matter tracers (galaxy, CMB, lenses, Ly-alpha) are spatially distributed in the universe as a function of time and over distances of hundreds of million of light-years. He has worked on theory, analytical predictions, statistical analysis, numerical integration, N-body and Monte-Carlo simulations, analysis of large databases, parameter estimation, raw observations, data reduction, teaching and divulgation. He has also participated and supported technical developments related to instrumentation, data reduction and software design, and served in several steering, science, organizing and managing committees. Currently, he is PI of the Spanish consortium of the DES and PAU survey, two surveys intended to search and unveil the mysteries behind the dark energy and dark matter of our Universe.