Cosmology from CMB and Large-scale Structures with New and Old Probes

04 Mar 2025
Seminars and colloquia
Time
Venue
Beecroft Seminar Room
Denys Wilkinson Building, Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH
Speaker(s)

Giulio Fabbian, Kavli Institute for Cosmology, Cambridge

Seminar series
Cosmology

Abstract

Cosmology is entering a new high precision era with the next generation CMB polarization experiments and galaxy surveys (Simons Observatory, CMB-S4, Euclid, Rubin). These experiments will cover a large fraction of the sky and will enable us to constrain cosmology from very large scales.  While waiting for these new data, we can prepare for the challenges that lie ahead looking at the current (or previous) generation of data in new ways. 

In this talk, I will discuss how the new Quaia catalog, the largest quasar catalog produced to date, can be used to constrain primordial non-Gaussianities in cross-correlation with CMB measurements, and show how upcoming Euclid data are expected to improve the constraining power of such measurements. In the second part of my talk I will focus on new probes of primordial and late time universe that can be extracted from CMB spectral distortion measurements. I will show how a re-analysis of archival data from the COBE/FIRAS mission and modern data analysis techniques allowed us to improve significantly the FIRAS original results. I will discuss in particular how these new results combined with hydrodynamical simulations can constrain feedback processes in galaxy formation and primordial non-Gaussianities at ultra small scales.