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arXiv · 1107.1186

Universal Amplitude Ratios in the Ising Model in Three Dimensions

A. Gordillo-Guerrero·R. Kenna·J. J. Ruiz-Lorenzo
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Abstract

We use a high-precision Monte Carlo simulation to determine the universal specific-heat amplitude ratio A+/A- in the three-dimensional Ising model via the impact angle ϕof complex temperature zeros. We also measure the correlation-length critical exponent νfrom finite-size scaling, and the specific-heat exponent αthrough hyperscaling. Extrapolations to the thermodynamic limit yield ϕ= 59.2(1.0) degrees, A+/A- = 0.56(3), ν= 0.63048(32) and α= 0.1086(10). These results are compatible with some previous estimates from a variety of sources and rule out recently conjectured exact values.

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A. Gordillo-Guerrero, R. Kenna, J. J. Ruiz-Lorenzo. 2011-11-22. Universal Amplitude Ratios in the Ising Model in Three Dimensions. https://doi.org/10.1088/1742-5468%2F2011%2F09%2Fp09019

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