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``Nowhere'' differentiable horizons

P. T. Chrusciel·G. J. Galloway
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Abstract

It is folklore knowledge amongst general relativists that horizons are well behaved, continuously differentiable hypersurfaces except perhaps on a negligible subset one needs not to bother with. We show that this is not the case, by constructing a Cauchy horizon, as well as a black hole event horizon, which contain no open subset on which they are differentiable.

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P. T. Chrusciel, G. J. Galloway. 1996-11-12. ``Nowhere'' differentiable horizons. https://doi.org/10.1007/s002200050336

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