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arXiv · hep-th/9701148

The Two-Dimensional O(2) Model on a Random Planar Lattice at Strong Coupling

A. Matytsin·P. Zaugg
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Abstract

The large spacing phase of the infinite random matrix chain, which represents the strongly coupled two-dimensional O(2) model on a random planar lattice, is explored. A class of solutions valid for large lattice spacings is constructed. It is proved that these solutions exhibit the critical exponents characteristic of pure two-dimensional gravity. The character expansion for the chain model is developed and an order parameter governing the Kosterlitz--Thouless phase transition is identified.

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A. Matytsin, P. Zaugg. 1997-01-27. The Two-Dimensional O(2) Model on a Random Planar Lattice at Strong Coupling. https://doi.org/10.1016/s0550-3213(97)00299-x

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