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arXiv · 1511.03755

Wormholes and nonsingular space-times in Palatini $f(R)$ gravity

Cosimo Bambi·Alejandro Cardenas-Avendano·Gonzalo J. Olmo·D. Rubiera-Garcia
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Abstract

We reconsider the problem of $f(R)$ theories of gravity coupled to Born-Infeld theory of electrodynamics formulated in a Palatini approach, where metric and connection are independent fields. By studying electrovacuum configurations in a static and spherically symmetric space-time, we find solutions which reduce to their Reissner-Nordström counterparts at large distances but undergo important non-perturbative modifications close to the center. Our new analysis reveals that the point-like singularity is replaced by a finite-size wormhole structure, which provides a geodesically complete and thus nonsingular space-time, despite the existence of curvature divergences at the wormhole throat. Implications of these results, in particular for the cosmic censorship conjecture, are discussed.

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Cosimo Bambi, Alejandro Cardenas-Avendano, Gonzalo J. Olmo, D. Rubiera-Garcia. 2016-03-07. Wormholes and nonsingular space-times in Palatini $f(R)$ gravity. https://doi.org/10.1103/physrevd.93.064016

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