Exploring Dark Matter with Improved Numerical Technique

08.03.2019 11:30 – 12:30

In this talk, I discuss several computational physics developments. The context is the study of potential dark matter observables calculated from traditional cosmological N-body simulations. While N-body simulations have been paramount to our understanding of the history of the Universe, they are often ill-suited to making local observations on small scales. This is due to particle-based sampling of the density field, which suffers from Poisson noise. Building on the phase space sheet (PSS) interpretation of Abel, Hahn and Kaehler (2012) of cold collisionless fluid, I develop a method for geometrically exact and robust volume- and point-sampling algorithms. These operate on a simplicial tessellation of a 3-manifold embedded in the 6-D phase space, such that the mass is interpolated between particles. The particles themselves are thus demoted from mass-carrying elements to Langrangian flow tracers. This discretization more accurately reflects the distribution of a cold fluid in phase space. The result is a smooth and continuous density field that aids accurate interpretations of cosmological dark matter simulations. I will discuss the application of these algorithmic developments to the indirect detection of dark matter (via decay and annihilation), studies of cosmic voids, the cosmic neutrino background, and simulations. I am excited about the general applications for these techniques, so I will end with a "wish list" of future research avenues.

Lieu

Bâtiment: Ecole de Physique

Salle 234, 24 quai Ernest-Ansermet

Organisé par

Département de physique théorique

Intervenant-e-s

Devon Powell, MPA Garching

entrée libre

Classement

Catégorie: Séminaire

Mots clés: dpt, Cosmology, LISA

Plus d'infos

cosmology.unige.ch/events/seminar

Contact: missing email