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→Introduction 引言
:<math>\label{eq:9}
:<math>\label{eq:9}
\alpha +2\beta +\gamma=2. </math>
\alpha +2\beta +\gamma=2. </math>
{{NumBlk|:|<math>\alpha +2\beta +\gamma=2. </math>|{{EquationRef|9}}}}When <math>2\beta+\gamma=2</math> the resulting <math>\alpha =0</math> means, generally, a logarithmic rather than power-law divergence together with a superimposed finite discontinuity occurring between <math>t=0+</math> and <math>t=0-</math> [4]. In the 2-dimensional Ising model the discontinuity is absent and only the logarithm remains, while in mean-field (van der Waals, Curie-Weiss, Bragg-Williams) approximation the logarithm is absent but the
由于<math>M = -(\partial
discontinuity is still present.
F/\partial H)_T\ ,</math>自由能<math>F</math>可以通过固定温度下积分由({{EquationNote|7}})式得出，且相应的热容<math>C_H = -(\partial ^2
F/\partial T^2)_H\ .</math>由({{EquationNote|7}})式可知，在<math>H=0</math>时<math>C_H</math>在临界点处成比例发散至<math>\mid t\mid ^{-\alpha}</math>（其中<math>t\rightarrow 0-</math>和<math>t\rightarrow
0+)\ </math>各有不同的系数），临界点指数<math>\alpha</math>与<math>\beta</math>和<math>\gamma</math>满足以下标度律：{{NumBlk|:|<math>\alpha +2\beta +\gamma=2. </math>|{{EquationRef|9}}}}When <math>2\beta+\gamma=2</math> the resulting <math>\alpha =0</math> means, generally, a logarithmic rather than power-law divergence together with a superimposed finite discontinuity occurring between <math>t=0+</math> and <math>t=0-</math> [4]. In the 2-dimensional Ising model the discontinuity is absent and only the logarithm remains, while in mean-field (van der Waals, Curie-Weiss, Bragg-Williams) approximation the logarithm is absent but the discontinuity is still present.
当<math>2\beta+\gamma=2</math>，则有<math>\alpha =0</math>，这通常意味着对数发散而不是幂律发散，并且在<math>t=0+</math>和<math>t=0-</math>之间存在叠加有限不连续。在二维伊辛模型中，仅有对数关系而这种不连续是不存在的；而在平均场近似中情形相反。
== Critical exponents ==
== Critical exponents ==