Multifield dynamics of supersymmetric Higgs inflation in SU(5) GUT
  We study the Higgs inflation model realized in the supersymmetric SU(5) grand
unified theory (GUT), focusing on its multifield dynamics and prediction of
cosmological observables. The requirement for GUT symmetry breaking during
inflation imposes tight constraints on the model parameters. We find,
nevertheless, with an appropriately chosen noncanonical Kahler potential the
model is in excellent agreement with the present cosmological observation. The
effects from multifield dynamics is found to be minor and thus, unlike other
similar supersymmetric implementation of nonminimally coupled Higgs inflation,
the prediction of this model is robust against multifield ambiguities.
