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Comment on gr-qc/0309003: ``Comment on `Absence of trapped surfaces and singularities in cylindrical collapse' ''

Sergio M. C. V. Goncalves
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Abstract

Very recently, a ``Comment'' by Wang [gr-qc/0309003] on a paper by Gonçalves [Phys. Rev. D {\bf 65}, 084045 (2002)] appeared, claiming that Gonçalves' analysis of trapped surfaces in certain kinds of cylindrical spacetimes was incomplete. Specifically, Wang claims to have found a coordinate extension of the spacetime used by Gonçalves (the Einstein-Rosen spacetime) which contains trapped surfaces; in addition, Wang also claims that some such trapped surfaces are apparent horizons. Here, I comment on Wang's ``Comment'', and argue that, while Wang's spacetime extension appears to exist and contain trapped surfaces, it does not render Gonçalves' results incomplete in the sense Wang claims. I also show that, contrary to Wang's claim, his spacetime extension does {\em not} contain apparent horizons, i.e., it does not contain outer marginally trapped surfaces which are the outer boundary of a trapped region. Further peripheral comments by Wang are also commented on.

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Sergio M. C. V. Goncalves. 2003-09-02. Comment on gr-qc/0309003: ``Comment on `Absence of trapped surfaces and singularities in cylindrical collapse' ''. https://arxiv.org/abs/gr-qc/0309013

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