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arXiv · 2210.15052

The Cauchy problem for Lorentzian Dirac operators under non-local boundary conditions

Christian Baer·Penelope Gehring
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Abstract

Non-local boundary conditions, such as the Atiyah-Patodi-Singer (APS) conditions, for Dirac operators on Riemannian manifolds are well understood while not much is known for such operators on spacetimes with timelike boundary. We define a class of Lorentzian boundary conditions that are local in time and non-local in the spatial directions and show that they lead to a well-posed Cauchy problem for the Dirac operator. This applies in particular to the APS conditions imposed on each level set of a given Cauchy temporal function.

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Christian Baer, Penelope Gehring. 2022-10-26. The Cauchy problem for Lorentzian Dirac operators under non-local boundary conditions. https://arxiv.org/abs/2210.15052

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