On the radius of injectivity of null hypersurfaces

S. Klainerman; I. Rodnianski

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On the radius of injectivity of null hypersurfaces

S. Klainerman·I. Rodnianski

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Abstract

The paper is concerned with regularity properties of boundaries of causal pasts of points in a 3+1-dimensional Einstein-vacuum spacetime. In a Lorentzian manifold such boundaries play crucial role in propagation of linear and nonlinear waves. We prove a uniform lower bound on the radius of injectivity of these null boundaries in terms of the Riemann curvature flux along them and some additional quantities arising specifically in a problem of a large data breakdown criterion in General Relativity

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S. Klainerman, I. Rodnianski. 2006-03-01. On the radius of injectivity of null hypersurfaces. https://arxiv.org/abs/math/0603010

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