Can we do accurate cosmology with galaxies?
12.05.2017 11:30 – 12:30
Upcoming projects such as Euclid, LSST, and DESI will measure positions and shapes for hundreds of millions of galaxies, enabling us to probe fundamental physics at an unprecedented level of precision with weak lensing and clustering analyses. However, in this new regime, several astrophysical effects must be understood to ensure that we draw accurate conclusions. I will discuss two such effects that can impact observed correlations on cosmological scales: intrinsic alignments (the shapes and orientations of galaxies) and galaxy biasing from streaming baryon velocities. Moreover, as combined analysis of multiple cosmological probes becomes standard, we must develop self-consistent modeling of several astrophysical effects. I will describe efforts to build multi-probe frameworks in both the ongoing Dark Energy Survey and in preparation for LSST. These frameworks include our FAST-PT algorithm for extremely efficient calculations in nonlinear perturbation theory.
Lieu
Bâtiment: Ecole de Physique
Salle 234, 24 quai Ernest-Ansermet
Organisé par
Département de physique théoriqueIntervenant-e-s
Jonathan A. Blazek, EPFL, Lausanneentrée libre