# Fastest curves and toroidal black holes

Banach Center Publications (1997)

- Volume: 41, Issue: 1, page 233-242
- ISSN: 0137-6934

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topWoolgar, E.. "Fastest curves and toroidal black holes." Banach Center Publications 41.1 (1997): 233-242. <http://eudml.org/doc/252220>.

@article{Woolgar1997,

abstract = {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.},

author = {Woolgar, E.},

journal = {Banach Center Publications},

keywords = {black hole horizons; spaces of complete causal curves; connectivity; active topological censorship; fastest curve arguments},

language = {eng},

number = {1},

pages = {233-242},

title = {Fastest curves and toroidal black holes},

url = {http://eudml.org/doc/252220},

volume = {41},

year = {1997},

}

TY - JOUR

AU - Woolgar, E.

TI - Fastest curves and toroidal black holes

JO - Banach Center Publications

PY - 1997

VL - 41

IS - 1

SP - 233

EP - 242

AB - 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.

LA - eng

KW - black hole horizons; spaces of complete causal curves; connectivity; active topological censorship; fastest curve arguments

UR - http://eudml.org/doc/252220

ER -

## References

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