Inflatable Dark Matter
  We describe a general scenario, dubbed "Inflatable Dark Matter", in which the
density of dark matter particles can be reduced through a short period of
late-time inflation in the early universe. The overproduction of dark matter
that is predicted within many otherwise well-motivated models of new physics
can be elegantly remedied within this context, without the need to tune
underlying parameters or to appeal to anthropic considerations. Thermal relics
that would otherwise be disfavored can easily be accommodated within this class
of scenarios, including dark matter candidates that are very heavy or very
light. Furthermore, the non-thermal abundance of GUT or Planck scale axions can
be brought to acceptable levels, without invoking anthropic tuning of initial
conditions. A period of late-time inflation could have occurred over a wide
range of scales from ~ MeV to the weak scale or above, and could have been
triggered by physics within a hidden sector, with small but not necessarily
negligible couplings to the Standard Model.
