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arXiv · 1902.07748

Taming Dirac strings and timelike loops in vacuum gravity

Suvikranth Gera·Sandipan Sengupta
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Abstract

The problem of singularities associated with Dirac strings and closed timelike curves in classical solutions of pure gravity is analyzed here. A method to eliminate these is introduced and established first for the Taub-NUT geometry. This is superceded by a smooth solution of first order field equations, which is defined to be a unique extension of the Taub Universe to a degenerate metric phase. As an additional feature, this framework naturally provides a geometric interpretation of the magnetic charge in the context of gravity theory without matter. Finally, exploiting the two phases of the metric determinant, we find a (smooth and unique) continuation of the Misner geometry as well, ridding it of closed timelike worldlines which exist in its otherwise Einsteinian manifestation.

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Suvikranth Gera, Sandipan Sengupta. 2019-02-20. Taming Dirac strings and timelike loops in vacuum gravity. https://doi.org/10.1103/physrevd.99.124038

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