11 Universal Amplitude Ratios in the Ising Model in Three Dimensions
A. Gordillo-Guerrero, Ralph Kenna B, Juan Jesus Ruiz-Lorenzo, F́ısica De Sistemas Complejos (bifi
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 phgr of complex temperature zeros. We also measure the correlation-length critical exponent ν from finite-size scaling and the specific-heat exponent α through hyperscaling. Extrapolations to the thermodynamic limit yield phgr = 59.2(1.0)°, A + /A − = 0.56(3), ν = 0.630 48(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.