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arXiv · hep-th/9507010

The Spin-Spin Correlation Function in the Two-Dimensional Ising Model in a Magnetic Field at $T=T_c$

G. Delfino·G. Mussardo
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Abstract

The form factor bootstrap approach is used to compute the exact contributions in the large distance expansion of the correlation function $<σ(x) σ(0)>$ of the two-dimensional Ising model in a magnetic field at $T=T_c$. The matrix elements of the magnetization operator $σ(x)$ present a rich analytic structure induced by the (multi) scattering processes of the eight massive particles of the model. The spectral representation series has a fast rate of convergence and perfectly agrees with the numerical determination of the correlation function.

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G. Delfino, G. Mussardo. 1995-07-03. The Spin-Spin Correlation Function in the Two-Dimensional Ising Model in a Magnetic Field at $T=T_c$. https://doi.org/10.1016/0550-3213(95)00464-4

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