Higher order spectra from an initially anisotropic universe
  In this paper, we present the higher order spectra of a scalar field produced
through the higher derivative interactions in the initially anisotropic
universe. Although we ignore the backreaction of the scalar field on the
geometry, our analysis should have much overlap with the quantum fluctuations
of the inflaton field in the anisotropic universe. We also include the planar
modes whose momenta are along the plane which is perpendicular to the
primordial preferred direction, for which effects of the initial anisotropy are
not suppressed. The presence of a negative frequency mode produces features
distinguishable from the case of the de Sitter inflation. We also show that
richer features appear in the trispectra due to the primordial anisotropy.
