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arXiv · 0709.2784

Putting a cap on causality violations in CDT

J. Ambjorn·R. Loll·W. Westra·S. Zohren
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Abstract

The formalism of causal dynamical triangulations (CDT) provides us with a non-perturbatively defined model of quantum gravity, where the sum over histories includes only causal space-time histories. Path integrals of CDT and their continuum limits have been studied in two, three and four dimensions. Here we investigate a generalization of the two-dimensional CDT model, where the causality constraint is partially lifted by introducing weighted branching points, and demonstrate that the system can be solved analytically in the genus-zero sector.

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J. Ambjorn, R. Loll, W. Westra, S. Zohren. 2007-09-18. Putting a cap on causality violations in CDT. https://doi.org/10.1088/1126-6708%2F2007%2F12%2F017

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