Gravitational Production of Superheavy Dark Matter and Associated
  Cosmological Signatures
  We study the gravitational production of super-Hubble-mass dark matter in the
very early universe. We first review the simplest scenario where dark matter is
produced mainly during slow roll inflation. Then we move on to consider the
cases where dark matter is produced during the transition period between
inflation and the subsequent cosmological evolution. The limits of smooth and
sudden transitions are studied, respectively. The relic abundances and the
cosmological collider signals are calculated.
