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arXiv · hep-th/0105269

On Brane Cosmology and Naked Singularities

Ph. Brax·A. C. Davis
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Abstract

Brane-world singularities are analysed, emphasizing the case of supergravity in singular spaces where the singularity puzzle is naturally resolved. These naked singularities are either time-like or null, corresponding to the finite or infinite amount of conformal time that massless particles take in order to reach them. Quantum mechanically we show that the brane-world naked singularities are inconsistent. Indeed we find that time-like singularities are not wave-regular, so the time-evolution of wave packets is not uniquely defined in their vicinity, while null singularities absorb incoming radiation. Finally we stress that for supergravity in singular spaces there is a topological obstruction, whereby naked singularities are necessarily screened off by the second boundary brane.

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Ph. Brax, A. C. Davis. 2001-05-28. On Brane Cosmology and Naked Singularities. https://doi.org/10.1016/s0370-2693(01)00734-1

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