Causal hierarchy of spacetimes, temporal functions and smoothness of Geroch’s splitting. A revision
نویسنده
چکیده
In the heroic epoch of Causality Theory, the problems concerning the smoothability of time functions and Cauchy hypersurfaces remained as unanswered folk questions. Just recently solved, our aim is to discuss the state of the art on this topic, including self-contained proofs for questions on causally continuous, stably causal and globally hyperbolic spacetimes.
منابع مشابه
Smooth globally hyperbolic splittings and temporal functions
Geroch’s theorem about the splitting of globally hyperbolic spacetimes is a central result in global Lorentzian Geometry. Nevertheless, this result was obtained at a topological level, and the possibility to obtain a metric (or, at least, smooth) version has been controversial since its publication in 1970. In fact, this problem has remained open until a definitive proof, recently provided by t...
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