We discuss an apparent paradox (and conjectured resolution) of Jacobson and Venkataramani concerning 'temporarily toroidal' black hole horizons, in light of a recent connectivity theorem for spaces of complete causal curves. We do this in a self-contained manner by first reviewing the 'fastest curve argument' which proves this connectivity theorem, and we note that active topological censorship can be derived as a corollary of this argument. We argue that the apparent paradox arises only when one dispenses with the invariant viewpoint provided by the connectivity theorem in favour of an observer-dependent description. Finally, we discuss an alternative to fastest curve arguments, which can be used to construct a self-contradictory null line in certain spacetimes violating topological censorship. These arguments may shed light on the relationship between topological and cosmic censorship.
@article{bwmeta1.element.bwnjournal-article-bcpv41z1p233bwm,
author = {Woolgar, E.},
title = {Fastest curves and toroidal black holes},
journal = {Banach Center Publications},
volume = {38},
year = {1997},
pages = {233-242},
zbl = {0887.53065},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-bcpv41z1p233bwm}
}
Woolgar, E. Fastest curves and toroidal black holes. Banach Center Publications, Tome 38 (1997) pp. 233-242. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-bcpv41z1p233bwm/
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