Anisotropic inflation with derivative couplings

摘要: We study anisotropic power-law inflationary solutions when the inflaton and its derivative couple to a vector field. This type of coupling is motivated by D-brane models, in which inflaton, field living on D-brane, disformally (derivatively). start studying phenomenological model where we show existence demonstrate their stability via dynamical system analysis. Compared case without coupling, anisotropy reduced thus can be made consistent with current limits, while value slow-roll parameter remains almost unchanged. also discuss for more general cases, including D-brane--like couplings.