Sachs-Wolfe effect in some anisotropic models
نویسندگان
چکیده
In this work it is shown that there are some spatially homogeneous but anisotropic models (Kantowski-Sachs and Bianchi type-III), with a positive cosmological constant, for which the inhomogeneities in the distribution of matter on the surface of the last scattering produce anisotropies (in large angular scales θ ∼ > 10 ◦) that do not differ from the ones produced in Friedmann-Lemâıtre-Robertson-Walker (FLRW) models, if the density parameters are finely tuned. Namely, for adiabatic initial conditions, the Sachs-Wolfe effect in these anisotropic models is equal to the one obtained for isotropic models: δT T = 1 3 Ψe + 2 r
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