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arXiv · hep-th/0004022

Brane surgery: energy conditions, traversable wormholes, and voids

Carlos Barcelo·Matt Visser
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Abstract

Branes are ubiquitous elements of any low-energy limit of string theory. We point out that negative tension branes violate all the standard energy conditions of the higher-dimensional spacetime they are embedded in; this opens the door to very peculiar solutions of the higher-dimensional Einstein equations. Building upon the (3+1)-dimensional implementation of fundamental string theory, we illustrate the possibilities by considering a toy model consisting of a (2+1)-dimensional brane propagating through our observable (3+1)-dimensional universe. Developing a notion of "brane surgery", based on the Israel--Lanczos--Sen "thin shell" formalism of general relativity, we analyze the dynamics and find traversable wormholes, closed baby universes, voids (holes in the spacetime manifold), and an evasion (not a violation) of both the singularity theorems and the positive mass theorem. These features appear generic to any D-brane model that permits negative tension branes: This includes the Randall--Sundrum models and their variants.

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Carlos Barcelo, Matt Visser. 2000-05-08. Brane surgery: energy conditions, traversable wormholes, and voids. https://doi.org/10.1016/s0550-3213(00)00379-5

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