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arXiv · 1401.4227

Observational distinction between black holes and naked singularities: the role of the redshift function

Néstor Ortiz·Olivier Sarbach·Thomas Zannias
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Abstract

We suggest that the redshift of photons traveling from past to future null infinity through a collapsing object could provide an observational signature capable of differentiating between the formation of a globally naked singularity and the formation of an event horizon. Supporting evidence for this idea is drawn from the analysis of photons with zero angular momentum through the center of a collapsing spherical dust cloud. We show that the frequency shift as a function of proper time with respect to stationary observers has distinct features depending on whether the object collapses to a black hole or a naked singularity.

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Néstor Ortiz, Olivier Sarbach, Thomas Zannias. 2014-01-17. Observational distinction between black holes and naked singularities: the role of the redshift function. https://doi.org/10.1088/0264-9381/32/24/247001

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