Fermionic Path Integrals and Two-Dimensional Ising Model with Quenched Site Disorder

V. N. Plechko

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arXiv · hep-th/9906107

Fermionic Path Integrals and Two-Dimensional Ising Model with Quenched Site Disorder

V. N. Plechko

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Abstract

The notion of the integral over the anticommuting Grassmann variables is applied to analyze the fermionic structure of the 2D Ising model with quenched site dilution. In the $N$-replica scheme, the model is explicitly reformulated as a theory of interacting fermions on a lattice. For weak dilution, the continuum-limit approximation implies the log-log singularity in the specific heat near $T_c$.

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V. N. Plechko. 1999-06-15. Fermionic Path Integrals and Two-Dimensional Ising Model with Quenched Site Disorder. https://arxiv.org/abs/hep-th/9906107

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