Gravitational lensing by compact objects within plasma
Abstract
Frequency-dependent gravitational lens effects are found for trajectories of electromagnetic rays passing through a distribution of plasma near a massive object. Ray propagation through plasma adds extra terms to the equations of motion that depend on the plasma refractive index. For low-frequency rays these refractive effects can dominate, turning the gravitational lens into a mirror. While light rays behave like particles with an effective mass given by the plasma frequency in a medium with constant density, an inhomogeneous plasma introduces more complicated behavior even for the spherically symmetric case. As a physical example, the pulse profile of a compact object sheathed in a dense plasma is examined, which introduces dramatic frequency-dependent shifts from the behavior in vacuum.
Cite
@article{arxiv.1611.00076,
title = {Gravitational lensing by compact objects within plasma},
author = {Adam Rogers},
journal= {arXiv preprint arXiv:1611.00076},
year = {2016}
}
Comments
8 pages, 2 figures. Summary of an invited parallel session talk given in the GL3 session at the 14th Marcel Grossmann meeting, University of Rome "La Sapienza", Rome, July 12-18, 2015. For more details, see A. Rogers, 2015, MNRAS, 451, 1, 17-25