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arXiv · 2005.01477

Skew Killing spinors in four dimensions

Nicolas Ginoux·Georges Habib·Ines Kath
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Abstract

This paper is devoted to the classification of 4-dimensional Riemannian spin manifolds carrying skew Killing spinors. A skew Killing spinor $ψ$ is a spinor that satisfies the equation $\nabla$X$ψ$ = AX $\times$ $ψ$ with a skew-symmetric endomorphism A. We consider the degenerate case, where the rank of A is at most two everywhere and the non-degenerate case, where the rank of A is four everywhere. We prove that in the degenerate case the manifold is locally isometric to the Riemannian product R x N with N having a skew Killing spinor and we explain under which conditions on the spinor the special case of a local isometry to S 2 x R 2 occurs. In the non-degenerate case, the existence of skew Killing spinors is related to doubly warped products whose defining data we will describe.

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Nicolas Ginoux, Georges Habib, Ines Kath. 2020-07-27. Skew Killing spinors in four dimensions. https://arxiv.org/abs/2005.01477

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