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arXiv · 1901.03733

Spatial dispersion of light rays propagating through a plasma in Kerr spacetime

Tom Kimpson·Kinwah Wu·Silvia Zane
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Abstract

We investigate the propagation of light through a plasma on a background Kerr spacetime via a Hamiltonian formulation. The behaviour of light when propagating through a vacuum and through a plasma is not the same; the convolution of gravitational and plasma effects gives rise to a dispersion in both space and time. The magnitude of the dispersion is a strong function of both the ray frequency and impact parameter. We discuss implications for the detection of gravitationally bent pulsar beams near the Galactic centre.

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Tom Kimpson, Kinwah Wu, Silvia Zane. 2019-01-11. Spatial dispersion of light rays propagating through a plasma in Kerr spacetime. https://doi.org/10.1093/mnras/stz138

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