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Sum over topologies and double-scaling limit in 2D Lorentzian quantum gravity

R. Loll·W. Westra
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Abstract

We construct a combined non-perturbative path integral over geometries and topologies for two-dimensional Lorentzian quantum gravity. The Lorentzian structure is used in an essential way to exclude geometries with unacceptably large causality violations. The remaining sum can be performed analytically and possesses a unique and well-defined double-scaling limit, a property which has eluded similar models of Euclidean quantum gravity in the past.

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R. Loll, W. Westra. 2005-07-01. Sum over topologies and double-scaling limit in 2D Lorentzian quantum gravity. https://doi.org/10.1088/0264-9381%2F23%2F2%2F011

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