Name: Masaaki Watanabe
 Institution: Kyoto University, Depertment of Physics
 Title: Anisotropic inflation and its imprints on the CMB
 Key Words: inflation, statistical anisotropy, cosmic microwave background radiation
 Abstract: The standard model of inflation predicts statistical isotropy of the primordial density fluctuation, while forthcoming observations of the cosmic microwave background radiation (CMB) are able to detect a slight deviation from it.
In this talk, I propose an inflationary model in which a vector field is coupled to the scalar inflaton field. Analysis of homogeneous background shows that small but finite anisotropy in cosmic expansion is realized throughout the inflation for certain forms of the coupling. Linear perturbation tells that this induces statistical anisotropy in the primordial density fluctuation. In addition, sizable amount of cross correlation between density perturbation and a polarization of gravitational wave is predicted.
I also discuss their imprints on CMB temperature and polarization anisotropies and prospects for the constraint gained by future observations.