paper

Can primordial parity violation explain the observed cosmic birefringence?

arXiv:2208.08101 · doi:10.1103/PhysRevD.106.103529

Abstract

Recently, the cross-correlation between - and -mode polarization of the cosmic microwave background (CMB), which is well explained by cosmic birefringence with rotation angle deg, has been found in CMB polarization data. We carefully investigate the possibility of explaining the observed correlation by the primordial chiral gravitational waves (CGWs), which can be generated in the parity-violating theories in the primordial Universe. We found that the CGWs scenario does not work due to the overproduction of the auto-correlation which far exceeds the observed one by SPTPol and POLARBEAR.

5 pages, 2 figures

References in corpus (6)

Can primordial parity violation explain the observed cosmic birefringence? · wovepaper