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arXiv · 1412.6104

Chiral Imprint of a Cosmic Gauge Field on Primordial Gravitational Waves

Jannis Bielefeld·Robert R. Caldwell
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Abstract

A cosmological gauge field with isotropic stress-energy introduces parity violation into the behavior of gravitational waves. We show that a primordial spectrum of inflationary gravitational waves develops a preferred handedness, left- or right-circularly polarized, depending on the abundance and coupling of the gauge field during the radiation era. A modest abundance of the gauge field would induce parity-violating correlations of the cosmic microwave background temperature and polarization patterns that could be detected by current and future experiments.

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Jannis Bielefeld, Robert R. Caldwell. 2014-12-18. Chiral Imprint of a Cosmic Gauge Field on Primordial Gravitational Waves. https://doi.org/10.1103/physrevd.91.123501

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