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arXiv · 0810.2503

A Causal Alternative for c=0 Strings

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

We review a recently discovered continuum limit for the one-matrix model which describes "causal" two-dimensional quantum gravity. The behaviour of the quantum geometry in this limit is different from the quantum geometry of Euclidean two-dimensional quantum gravity defined by taking the "standard" continuum limit of the one-matrix model. Geodesic distance and time scale with canonical dimensions in this new limit, contrary to the situation in Euclidean two-dimensional quantum gravity. Remarkably, whenever we compare, the known results of (generalized) causal dynamical triangulations are reproduced exactly by the one-matrix model. We complement previous results by giving a geometrical interpretation of the new model in terms of a generalization of the loop equation of Euclidean dynamical triangulations. In addition, we discuss the time evolution of the quantum geometry.

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J. Ambjorn, R. Loll, Y. Watabiki, W. Westra, S. Zohren. 2008-10-14. A Causal Alternative for c=0 Strings. https://arxiv.org/abs/0810.2503

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