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arXiv · 0806.3082

Anomalous CMB polarization and gravitational chirality

Carlo R. Contaldi·Joao Magueijo·Lee Smolin
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Abstract

We consider the possibility that gravity breaks parity, with left and right handed gravitons coupling to matter with a different Newton's constant and show that this would affect their zero-point vacuum fluctuations during inflation. Should there be a cosmic background of gravity waves, the effect would translate into anomalous CMB polarization. Non-vanishing TB (and EB) polarization components emerge, revealing interesting experimental targets. Indeed if reasonable chirality is present a TB measurement would provide the easiest way to detect a gravitational wave background. We speculate on the theoretical implications of such an observation.

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Carlo R. Contaldi, Joao Magueijo, Lee Smolin. 2008-06-18. Anomalous CMB polarization and gravitational chirality. https://doi.org/10.1103/physrevlett.101.141101

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