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arXiv · hep-lat/9512002

Ising Spins on a Gravitating Sphere

Christian Holm·Wolfhard Janke
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Abstract

We investigated numerically an Ising model coupled to two-dimensional Euclidean gravity with spherical topology, using Regge calculus with the $dl/l$ path-integral measure to discretize the gravitational interaction. Previous studies of this system with toroidal topology have shown that the critical behavior of the Ising model remains in the flat-space Onsager universality class, contrary to the predictions of conformal field theory and matrix models. Implementing the spherical topology as triangulated surfaces of three-dimensional cubes, we find again strong evidence that the critical exponents of the Ising transition are consistent with the Onsager values, and that KPZ exponents are definitely excluded.

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Christian Holm, Wolfhard Janke. 1995-12-01. Ising Spins on a Gravitating Sphere. https://doi.org/10.1016/0370-2693(96)00199-2

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