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arXiv · gr-qc/0307022

Electromagnetic waves around dilatonic stars and naked singularities

Roberto Casadio·Sergio Fabi·Benjamin Harms
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Abstract

We study the propagation of classical electromagnetic waves on the simplest four-dimensional spherically symmetric metric with a dilaton background field. Solutions to the relevant equations are obtained perturbatively in a parameter which measures the strength of the dilaton field (hence parameterizes the departure from Schwarzschild geometry). The loss of energy from outgoing modes is estimated as a back-scattering process against the dilaton background, which would affect the luminosity of stars with a dilaton field. The radiation emitted by a freely falling point-like source on such a background is also studied by analytical and numerical methods.

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Roberto Casadio, Sergio Fabi, Benjamin Harms. 2003-07-07. Electromagnetic waves around dilatonic stars and naked singularities. https://doi.org/10.1103/physrevd.70.044026

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