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arXiv · 1306.6769

Nonsingular electrovacuum solutions with dynamically generated cosmological constant

E. I. Guendelman·Gonzalo J. Olmo·D. Rubiera-Garcia·M. Vasihoun
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Abstract

We consider static spherically symmetric configurations in a Palatini extension of General Relativity including $R^2$ and Ricci-squared terms, which is known to replace the central singularity by a wormhole in the electrovacuum case. We modify the matter sector of the theory by adding to the usual Maxwell term a nonlinear electromagnetic extension which is known to implement a confinement mechanism in flat space. One feature of the resulting theory is that the non-linear electric field leads to a dynamically generated cosmological constant. We show that with this matter source the solutions of the model are asymptotically de Sitter and possess a wormhole topology. We discuss in some detail the conditions that guarantee the absence of singularities and of traversable wormholes.

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E. I. Guendelman, Gonzalo J. Olmo, D. Rubiera-Garcia, M. Vasihoun. 2013-10-26. Nonsingular electrovacuum solutions with dynamically generated cosmological constant. https://doi.org/10.1016/j.physletb.2013.09.039

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