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arXiv · hep-lat/9708014

Complex zeros of the 2d Ising model on dynamical random lattices

J. Ambjørn·K. N. Anagnostopoulos·U. Magnea
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Abstract

We study the zeros in the complex plane of the partition function for the Ising model coupled to $2d$ quantum gravity for complex magnetic field and for complex temperature. We compute the zeros by using the exact solution coming from a two matrix model and by Monte Carlo simulations of Ising spins on dynamical triangulations. We present evidence that the zeros form simple one-dimensional patterns in the complex plane, and that the critical behaviour of the system is governed by the scaling of the distribution of singularities near the critical point.

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J. Ambjørn, K. N. Anagnostopoulos, U. Magnea. 1997-08-20. Complex zeros of the 2d Ising model on dynamical random lattices. https://doi.org/10.1016/s0920-5632(97)00893-1

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