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**On the polarization of gravitational waves.**
*(English)*
Zbl 1217.83027

Mladenov, Ivaïlo M. (ed.), Proceedings of the 9th international conference on geometry, integrability and quantization, Sts. Constantine and Elena, Bulgaria, June 8–13, 2007. Sofia: Bulgarian Academy of Sciences (ISBN 978-954-8495-42-4/pbk). 320-333 (2008).

A gravitational field that is invariant with respect to a non-Abelian two-dimensional Lie algebra whose generator is light like is characterized from a geometric point of view. It represents a spin-1 gravitational wave (of Petrov type \(N\)) propagating at light velocity. It is weaker than a spin-2 gravitational wave. Its metric in the harmonic coordinates has off-diagonal form and its (non-globally square integrable spin-1) perturbation has only one index in the plane orthogonal to the propagation direction. Non-singular spin-1 gravitational waves are those with a matter source.

Spin-1 gravitational waves are also analyzed using the gravitoelectromagnetic perspective, and the photon-photon gravitational interaction is also studied.

For the entire collection see [Zbl 1154.17001].

Spin-1 gravitational waves are also analyzed using the gravitoelectromagnetic perspective, and the photon-photon gravitational interaction is also studied.

For the entire collection see [Zbl 1154.17001].

Reviewer: Alena Pravdová (Praha)

### MSC:

83C35 | Gravitational waves |

83C20 | Classes of solutions; algebraically special solutions, metrics with symmetries for problems in general relativity and gravitational theory |

83C25 | Approximation procedures, weak fields in general relativity and gravitational theory |

83C50 | Electromagnetic fields in general relativity and gravitational theory |

83C10 | Equations of motion in general relativity and gravitational theory |