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Second-order gravitational effects of local inhomogeneities on CMB anisotropies in nonzero-Lambda flat cosmological models

Kenji Tomita
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Abstract

Nonlinear gravitational effects of large-scale inhomogeneities on Cosmic Microwave Background (CMB) anisotropies are studied. based on the relativistic second-order theory of perturbations in nonzero-Lambda flat cosmological models, which has been analytically derived by the present author, and on the second-order formula of CMB anisotropies derived by Mollerach and Matarrese. In this paper we derive the components of the CMB anisotropy power spectra in the range of l = 1 -22 which are caused by asymmetric local inhomogeneities on scales of 300 Mpc. Using our results it is found that there is a possibility to explain the small north-south asymmetry of CMB anisotropies which has recently been observed.

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Kenji Tomita. 2006-01-06. Second-order gravitational effects of local inhomogeneities on CMB anisotropies in nonzero-Lambda flat cosmological models. https://doi.org/10.1103/physrevd.72.043526

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