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arXiv · 1912.12903

Dark Ultra-Light Scalars and Cosmic Parity Violation

Seokcheon Lee·Guo-Chin Liu·Kin-Wang Ng
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Abstract

If the dark sector of the Universe consists of ultra-light scalars, their coupling to photon via a Chern-Simons term would induce a rotation of the polarization plane of the cosmic microwave background (CMB). This rotation would convert E -mode polarization into B -mode polarization, resulting in new CMB BB correlation and parity-violating TB and EB cross correlations. We review the subject giving details about the derivation of the rotational effects and summarizing the possible signals in current and future CMB B-mode experiments.

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Seokcheon Lee, Guo-Chin Liu, Kin-Wang Ng. 2019-12-30. Dark Ultra-Light Scalars and Cosmic Parity Violation. https://arxiv.org/abs/1912.12903

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