PIRSA:12100003

Video URL

https://pirsa.org/12100003

Maximum entropy, the universal dark matter density profile... and its destruction

Pontzen, A. (2012). Maximum entropy, the universal dark matter density profile... and its destruction. Perimeter Institute for Theoretical Physics. https://pirsa.org/12100003

Pontzen, Andrew. Maximum entropy, the universal dark matter density profile... and its destruction. Perimeter Institute for Theoretical Physics, Oct. 16, 2012, https://pirsa.org/12100003 

          @misc{ scivideos_PIRSA:12100003,
            doi = {10.48660/12100003},
            url = {https://pirsa.org/12100003},
            author = {Pontzen, Andrew},
            keywords = {Cosmology},
            language = {en},
            title = {Maximum entropy, the universal dark matter density profile... and its destruction},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2012},
            month = {oct},
            note = {PIRSA:12100003 see, \url{https://scivideos.org/index.php/pirsa/12100003}}
          }

Andrew Pontzen University of Oxford

Talk numberPIRSA:12100003
DOI10.48660/12100003
Source RepositoryPIRSA
Collection
Talk Type Scientific Series
Subject

Abstract

I review some recent developments in attempting to reconcile the observed galaxy population with numerical models of structure formation in the 'LCDM' concordance cosmology. Focussing on behaviour of dwarf galaxies, I describe the infamous 'cusp-core' dichotomy -- a long-standing challenge to the LCDM picture on small scales -- and use toy models to show how it is resolved in recent numerical simulations (Pontzen & Governato 2012). I then discuss the current observational status of this picture (Teyssier, Pontzen & Read 2012; Penarrubia et al 2012).

In the second half of the talk, I apply the analytic techniques developed for probing the effect of gas on dark matter dynamics to the question of how, in the absence of baryons, a universal "NFW" dark matter halo profile emerges (independent of scale or details of the initial conditions).

Thus the generation of NFW halos on the one hand and the destruction of their central cusps on the other can be ascribed to surprisingly similar physical arguments.