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General Relativistic Contribution to Polarization of the Cosmic Microwave Background Anisotropy

Subhendra Mohanty·A. R. Prasanna
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Abstract

We solve the wave equation for the electromagnetic field tensors associated with the CMBR photons in a universe with scalar metric perturbations. We show that the coupling of the electromagnetic fields with the curvature associated with the scalar perturbations gives rise to an optical rotation of the microwave background photons. The magnitude of the gravitationally generated V-Stokes parameter anisotropy $Δ_V$, is however very small compared to the linear polarisation caused by Thomson scattering.

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Subhendra Mohanty, A. R. Prasanna. 2000-10-06. General Relativistic Contribution to Polarization of the Cosmic Microwave Background Anisotropy. https://doi.org/10.1103/physrevd.63.027301

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