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Lorentzian 3d Gravity with Wormholes via Matrix Models

J. Ambjorn·J. Jurkiewicz·R. Loll·G. Vernizzi
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Abstract

We uncover a surprising correspondence between a non-perturbative formulation of three-dimensional Lorentzian quantum gravity and a hermitian two-matrix model with ABAB-interaction. The gravitational transfer matrix can be expressed as the logarithm of a two-matrix integral, and we deduce from the known structure of the latter that the model has two phases. In the phase of weak gravity, well-defined two-dimensional universes propagate in proper time, whereas in the strong-coupling phase the spatial hypersurfaces disintegrate into many components connected by wormholes.

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J. Ambjorn, J. Jurkiewicz, R. Loll, G. Vernizzi. 2001-06-11. Lorentzian 3d Gravity with Wormholes via Matrix Models. https://doi.org/10.1088/1126-6708%2F2001%2F09%2F022

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