Phase transition and monopole production in supergravity inflation
  In F-term supergravity inflation models, scalar fields other than the
inflaton generically receive a Hubble induced mass, which may restore gauge
symmetries during inflation and phase transitions may occur during or after
inflation as the Hubble parameter decreases. We study monopole (and domain
wall) production associated with such a phase transition in chaotic inflation
in supergravity and obtain a severe constraint on the symmetry breaking scale
which is related with the tensor-to-scalar ratio. Depending on model
parameters, it is possible that monopoles are sufficiently diluted to be free
from current constraints but still observable by planned experiments.
