Cosmology on small scales: the structure of (mostly) dark matter halos
Carlos Frenk (University of Durham)
The standard model of cosmology -- the ``Lambda cold dark matter'' model
-- is based on the idea that the dark matter is a collisionless elementary
particle, probably a supersymmetric particle. This model (which mostly
dates back to the 1980s) has been famously verified by observations of the
cosmic microwave background radiation and the large-scale distribution of
galaxies. However, the model has yet to be tested conclusively on the
small scales appropriate to most astronomical objects, such as galaxies
and clusters. I will review our current understanding of the distribution
of dark matter on small scales which derives largely from large
cosmological N-body simulations and I will discuss prospects for detecting
dark matter, either through its gravitational effect on galaxies and
clusters or, more directly, through gamma-ray annihilation radiation.