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arXiv · 2404.05883

Twistor initial data characterisation of pp-waves

Edgar Gasperin·Francisco Pais
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Abstract

This note gives a concise derivation of a twistor-initial-data characterisation of pp-wave spacetimes in vacuum. The construction is based on a similar calculation for the Minkowski spacetime in [Class. Quantum Grav. 28 075010]. The key difference is that for the Minkowski spacetime a necessary condition is that $\nabla_{A}{}^{A'}\bar{\kappa}_{A'} \neq 0$. In this note it is shown that if $\nabla_{A}{}^{A'}\bar{\kappa}_{A'}=0$ then the development is a pp-wave spacetime. Furthermore, it is shown that such condition propagates off the initial hypersurface, which, in turn, gives a twistor initial data characterisation of pp-waves.

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Edgar Gasperin, Francisco Pais. 2024-04-08. Twistor initial data characterisation of pp-waves. https://doi.org/10.1088/1361-6382/ad3b5e

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