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arXiv · hep-lat/9709072

Beyond the c=1 Barrier in Two-Dimensional Quantum Gravity

G. Thorleifsson·B. Petersson
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Abstract

We introduce a simple model of touching random surfaces, by adding a chemical potential rho for ``minimal necks'', and study this model numerically coupled to a Gaussian model in d-dimensions (for central charge c = d = 0, 1 and 2). For c <= 1, this model has a phase transition to branched polymers, for sufficiently large rho. For c = 2, however, the extensive simulations indicate that this transition is replaced by a cross-over behavior on finite lattices --- the model is always in the branched polymer phase. This supports recent speculations that, in 2d-gravity, the behavior observe in simulations for $c \leq 1$, is dominated by finite size effects, which are exponentially enhanced as c -> 1+.

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G. Thorleifsson, B. Petersson. 1997-09-20. Beyond the c=1 Barrier in Two-Dimensional Quantum Gravity. https://doi.org/10.1016/s0920-5632(97)00891-8

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