Pure Gravity Mediation and Chaotic Inflation in Supergravity
  We investigate compatibility of the pure gravity mediation (or the minimal
split supersymmetry) with chaotic inflation models in supergravity. We find
that an approximate Z2 parity of the inflaton is useful to suppress gravitino
production from thermal bath and to obtain consistent inflation dynamics. We
discuss production of the lightest supersymmetric particle through the decay of
the inflaton with the approximate Z2 symmetry and find that a large gravitino
mass is favored to avoid the overproduction of the lightest supersymmetric
particle, while a lower gravitino mass requires tuning of parameters. This may
explain why the nature has chosen the gravitino mass of O(100) TeV rather than
O(100) GeV.
