SÉMINAIRE DU GRECO
"Large scale structure formation with the Schrödinger method" 

C. Uhlemann 

When describing largescale structure formation of collisionless dark matter one is interested in the dynamics of a large collection of identical point particles that interact only gravitationally. Via gravitational instability initially small density perturbations evolve into eventually bound structures, like dark matter halos that are distributed along the cosmic web. Even though this problem seems quite simple from a conceptual point of view, no sufficiently general solution of the underlying equation, the collisionless Boltzmann equation coupled to the Poisson equation, is known. Therefore one usually has to resort to Nbody simulations which tackle the problem numerically. Analytical methods to describe structure formation are in general based on the dust model which describes cold dark matter as a pressureless fluid characterized by density and velocity. This model works quite well up to the quasilinear regime but eventually fails when multiple streams form that are especially important for halo formation but lead to singularities in the model.


lundi 28 septembre 2015  11:00 Salle des séminaires Évry Schatzman, Institut d'Astrophysique de Paris 
