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arXiv · 1506.08550

Does the Gauss-Bonnet term stabilize wormholes?

Takafumi Kokubu·Hideki Maeda·Tomohiro Harada
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Abstract

The effect of the Gauss-Bonnet term on the existence and dynamical stability of thin-shell wormholes as negative tension branes is studied in the arbitrary dimensional spherically, planar, and hyperbolically symmetric spacetimes. We consider radial perturbations against the shell for the solutions which have the Z${}_2$ symmetry and admit the general relativistic limit. It is shown that the Gauss-Bonnet term shrinks the parameter region admitting static wormholes. The effect of the Gauss-Bonnet term on the stability depends on the spacetime symmetry. For planar symmetric wormholes, the Gauss-Bonnet term does not affect their stability. If the coupling constant is positive but small, the Gauss-Bonnet term tends to destabilize spherically symmetric wormholes, while it stabilizes hypebolically symmetric wormholes. The Gauss-Bonnet term can destabilize hypebolically symmetric wormholes as a non-perturbative effect, however, spherically symmetric wormholes cannot be stable.

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Takafumi Kokubu, Hideki Maeda, Tomohiro Harada. 2015-06-29. Does the Gauss-Bonnet term stabilize wormholes?. https://doi.org/10.1088/0264-9381/32/23/235021

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