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arXiv · gr-qc/9811052

The gravitational interaction of light: from weak to strong fields

V. Faraoni·R. M. Dumse
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Abstract

An explanation is proposed for the fact that pp-waves superpose linearly when they propagate parallely, while they interact nonlinearly, scatter and form singularities or Cauchy horizons if they are antiparallel. Parallel pp-waves do interact, but a generalized gravitoelectric force is exactly cancelled by a gravitomagnetic force. In an analogy, the interaction of light beams in linearized general relativity is also revisited and clarified, a new result is obtained for photon to photon attraction, and a conjecture is proved. Given equal energy density in the beams, the light-to-light attraction is twice the matter-to-light attraction and four times the matter-to-matter attraction.

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V. Faraoni, R. M. Dumse. 1998-11-16. The gravitational interaction of light: from weak to strong fields. https://doi.org/10.1023/a%3A1018867405133

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