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arXiv · 2304.02331

Initial data rigidity via Dirac-Witten operators

Jonathan Glöckle
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Abstract

In this paper we prove an initial data rigidity result \`a la Eichmair, Galloway and Mendes (arXiv:2009.09527) using Dirac operator techniques. It applies to initial data sets on spin bands that satisfy the dominant energy condition, a boundary condition for the future null expansion scalar and the $\hat{A}$-obstruction for positive scalar curvature on one of the boundary pieces. Interestingly, these bands turn out to carry lightlike imaginary $W$-Killing spinors, which are connected to Lorentzian special holonomy and moduli spaces of Ricci-flat metrics. We also obtain slight generalizations of known rigidity results on Riemannian bands.

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Jonathan Glöckle. 2023-04-05. Initial data rigidity via Dirac-Witten operators. https://arxiv.org/abs/2304.02331

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