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arXiv · hep-th/9209085

Ising Model and $N=2$ Supersymmetric Theories

S. Cecotti·C. Vafa
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Abstract

We establish a direct link between massive Ising model and arbitrary massive $N=2$ supersymmetric QFT's in two dimensions. This explains why the equations which appear in the computation of spin-correlations in the non-critical Ising model are the same as those describing the geometry of vacua in $N=2$ theories. The tau-function appearing in the Ising model (i.e., the spin correlation function) is reinterpreted in the $N=2$ context as a new `index'. In special cases this new index is related to Ray-Singer analytic torsion, and can be viewed as a generalization of that to loop space of Kähler manifolds.

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S. Cecotti, C. Vafa. 1992-09-22. Ising Model and $N=2$ Supersymmetric Theories. https://doi.org/10.1007/bf02098023

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