Abstract
We propose a hoop conjecture in the presence of a positive cosmological constant Λ: when an apparent horizon forms in a gravitational collapse, the matter must be sufficiently compactified such that the circumference scrC satisfies the condition scrC≲4πM≲4π, where M is the Abbott-Deser mass of the collapsed body and =1/3 √Λ . To confirm our conjecture, we investigate two cases: (1) initial data of a prolate or oblate dust spheroid, and (2) the Kastor-Traschen spacetime which describes a black hole collision with Λ. We also discuss a relation between the hoop conjecture and an appearance of a naked singularity.
- Received 11 April 1994
DOI:https://doi.org/10.1103/PhysRevD.50.4903
©1994 American Physical Society