Chiral Imprint of a Cosmic Gauge Field on Primordial Gravitational Waves
arXiv:1412.6104 · doi:10.1103/PhysRevD.91.123501
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.
5 pages, 6 figures