Gravitational Scattering Of Photons Off Cosmic Strings
arXiv:1302.3222 · doi:10.1103/PhysRevD.87.083512
Abstract
Photons can gravitationally scatter off a cosmic string loop and gain or lose energy. We consider the spectral distortion induced by cosmic string loops placed in an ambient thermal bath of photons. The fractional deviation from a thermal spectrum caused by cosmic strings is estimated to scale as (G_N μ)^2 z^2, where G_N is Newton's constant, is the string tension, and z is the cosmological redshift after which spectral distortions can survive. This effect is large enough to potentially be of observational interest.
10 pages, 2 figures