Erratum: Gravitational collapse of cylindrical shells made of counterrotating dust particles [Phys. Rev. D62, 124001 (2000)]

Abstract

͑2͒ In Eq. ͑29͒ the expression for p z should take the formwhile the ones for and p remain the same. ͑3͒ Equation ͑30͒ should be written asshould be replaced by ͑33͒The rest of the paper, including the conclusions, remains the same.

No-Go theorem in spacetimes with two commuting spacelike killing vectors

“…Degenerate apparent horizons can be formed only in the cases where Λ ≤ 0. These are consistent with all the results obtained so far in the studies of both stationary black holes [19,20,27] and gravitational collapse [21,24,25]. In particular, it supports the hoop conjecture [2].…”

Spectrum of end states of gravitational collapse with tangential stresses

“…There remains the possibility that such naked singularities are an artifact of spherical symmetry by itself, although both numerical and analytical results suggest that dynamical curvature singularities may persist in non-spherical collapse [21,22,23].…”

Absence of trapped surfaces and singularities in cylindrical collapse

“…The case of counter-rotating dust coupled to Einstein-Rosen waves was addressed by Apostolatos and Thorne [11], who resorted to sequences of momentarily static radiation-free (MSRF) configurations and C-energy balance arguments to conclude that an arbitrarily small amount of counter-rotation (and, very likely, also of net rotation) suffices to halt collapse, thereby precluding the formation of spindle singularities. The counter-rotating case was recently revisited by Pereira and Wang [36], who considered a flat interior and an outgoing null fluid exterior (as opposed to a 'realistic' vacuum containing cylindrical waves); by means of further assumptions for the matter content, they obtained a simple solvable model which admits initial data leading to a spindle singularity, thus in apparent contradiction with the earlier results. However, the model is highly contrived, and the assumptions made render it unphysical, since the dynamics of the exterior null fluid can only be obtained a posteriori, after a particular solution for the motion of the shell is derived.…”