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arXiv · 1001.4172

Last scattering, relic gravitons and the circular polarization of the CMB

Massimo Giovannini
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Abstract

The tensor contribution to the $V$-mode polarization induced by a magnetized plasma at last scattering vanishes exactly. Conversely a polarized background of relic gravitons cannot generate a $V$-mode polarization. The reported results suggest that, in the magnetized $Λ$CDM paradigm, the dominant source of circular dichroism stems from the large-scale fluctuations of the spatial curvature.

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Massimo Giovannini. 2010-01-23. Last scattering, relic gravitons and the circular polarization of the CMB. https://doi.org/10.1103/physrevd.81.123003

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