The Missing Link Between Dark Matter And Structure Formation

Recording Details

Speaker(s): 
Scientific Areas: 
Collection/Series: 
PIRSA Number: 
06100015

Abstract

Weakly interacting massive particles (WIMPs) are excellent candidates
for cold dark matter. After the first millisecond, WIMPs have
decoupled from standard model matter, both chemically and
kinetically, they enter the free streaming regime and the formation
of cosmic structure begins. Another 40 million years pass before the
typical first structures enter the nonlinear regime and collapse to
the first WIMPy halos. Therefore, it has been assumed that structure
formation is insensitive to the WIMP field theory and can be
neglected. However,
this leads to a monotonically increasing power of structure formation
on small scales and some kind of regularization procedure would be
required to make the hierarchical picture of structure formation well
defined. It will be shown that nonequilibrium processes give rise to
a physical regularization of hierarchical structure formation. This
has important consequences for indirect and direct dark matter searches which are sensitive to sub-galactic and sub-milli-parsec scales.
Furthermore, due the existence of a physical regulator, the problem
of structure formation can consistently be solved using N-body
simulations.