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arXiv · hep-lat/9307016

On Spin and Matrix Models in the Complex Plane

Poul H. Damgaard·Urs M. Heller
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Abstract

We describe various aspects of statistical mechanics defined in the complex temperature or coupling-constant plane. Using exactly solvable models, we analyse such aspects as renormalization group flows in the complex plane, the distribution of partition function zeros, and the question of new coupling-constant symmetries of complex-plane spin models. The double-scaling form of matrix models is shown to be exactly equivalent to finite-size scaling of 2-dimensional spin systems. This is used to show that the string susceptibility exponents derived from matrix models can be obtained numerically with very high accuracy from the scaling of finite-$N$ partition function zeros in the complex plane.

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Poul H. Damgaard, Urs M. Heller. 1993-07-22. On Spin and Matrix Models in the Complex Plane. https://doi.org/10.1016/0550-3213(93)90526-u

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