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arXiv · 2204.13673

Parallel spinors, pp-waves, and gravitational perturbations

Bernardo Araneda
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Abstract

We prove that any real, vacuum gravitational perturbation of a 4-dimensional vacuum pp-wave space-time can be locally expressed, modulo gauge transformations, as the real part of a Hertz/Debye potential, where the scalar potential satisfies the wave equation. We discuss relations with complex perturbations, complex space-times, non-linear structures, and real spaces with split (ultra-hyperbolic/Kleinian) signature. Motivated by generalized notions of parallel spinors, we also discuss generalizations of the result to other space-times.

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Bernardo Araneda. 2022-04-28. Parallel spinors, pp-waves, and gravitational perturbations. https://doi.org/10.1088/1361-6382%2Facaa83

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