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arXiv · 1510.04228

Convex Functions and Geodesic Connectedness of Space-times

Stephanie B. Alexander·William A. Karr
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Abstract

This paper explores the relation between convex functions and the geometry of space-times and semi-Riemannian manifolds (an investigation initiated by Gibbons-Ishibashi). Specifically, we study geodesic connectedness. We give geometric-topological proofs of geodesic connectedness for classes of space-times to which known methods do not apply. For instance: A null-disprisoning space-time is geodesically connected if it supports a proper, nonnegative strictly convex function whose critical set is a point. Timelike strictly convex hypersurfaces of Minkowski space are geodesically connected. We also give a criterion for the existence of a convex function on a semi-Riemannian manifold. We compare our work with previously known results.

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Stephanie B. Alexander, William A. Karr. 2017-07-25. Convex Functions and Geodesic Connectedness of Space-times. https://arxiv.org/abs/1510.04228

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