Dark matter from scalar field fluctuations
  Dark matter (DM) may have its origin in a pre-Big Bang epoch, the cosmic
inflation. Here, we consider for the first time a broad class of scenarios
where a massive free scalar field unavoidably reaches an equilibrium between
its classical and quantum dynamics in a characteristic time scale during
inflation and sources the DM density. The study gives the abundance and
perturbation spectrum of any DM component sourced by the scalar field. We show
that this class of scenarios generically predicts enhanced structure formation,
allowing one to test models where DM interacts with matter only
gravitationally.
