# Injectivity Radius of Lorentzian Manifolds

@article{Chen2006InjectivityRO, title={Injectivity Radius of Lorentzian Manifolds}, author={Binglong Chen and Philippe G. LeFloch}, journal={Communications in Mathematical Physics}, year={2006}, volume={278}, pages={679-713} }

Motivated by the application to general relativity we study the geometry and regularity of Lorentzian manifolds under natural curvature and volume bounds, and we establish several injectivity radius estimates at a point or on the past null cone of a point. Our estimates are entirely local and geometric, and are formulated via a reference Riemannian metric that we canonically associate with a given observer (p, T) –where p is a point of the manifold and T is a future-oriented time-like unit…

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