Application of Gradient Expansion to Non-linear Gravitational Wave in Plane-symmetric Universe
نویسنده
چکیده
As an application of Gradient Expansion (long-wavelength) approximation , we studied the inhomogeneous universe including the gravitational wave(GW). For a plane-symmetric cosmological model, we could implement the 2nd order expansion and analyze the purely non-linear perturbation of GW. The result indicates that the non-linear eect plays an important role in anisotropic stage of the universe. We also conrm that the perturbation from the linear source term in gradient expansion is consistent with the result of linear perturbation.
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