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arXiv · 0905.2108

Summing over all Topologies in CDT String Field Theory

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

By explicitly allowing for topology to change as a function of time, two-dimensional quantum gravity defined through causal dynamical triangulations gives rise to a new continuum string field theory. Within a matrix-model formulation we show that -- rather remarkably -- the associated sum over all genera can be performed in closed form, leading to a nonperturbative definition of CDT string field theory. We also obtain explicit formulas for the n-loop correlation functions. Our construction exhibits interesting parallels with previous, purely Euclidean treatments.

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J. Ambjorn, R. Loll, W. Westra, S. Zohren. 2009-05-13. Summing over all Topologies in CDT String Field Theory. https://doi.org/10.1016/j.physletb.2009.06.031

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