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arXiv · 2607.12516

Submetries in non-positive signature and applications

Matteo Zanardini
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Abstract

We consider a generalization of the notion of submetry tailored to the setting of spacetimes. We show that, under suitable completeness assumptions, Lorentzian submetries between smooth spacetimes correspond to locally C^{1,1} Semi-Riemannian submersions. Moreover, we establish some applications regarding timelike curvature bounds, isometric group actions, acausal foliations and Lorentz-Wasserstein geometry.

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Matteo Zanardini. 2026-07-14. Submetries in non-positive signature and applications. https://arxiv.org/abs/2607.12516

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