标题： O(N+1) 对称二维非线性 sigma 模型的 1-圈有效作用量的解析计算 显示英文标题

标题： Analytic calculation of the 1-loop effective action for the O(N+1)-symmetric 2-dimensional nonlinear sigma-model

摘要： 通过对解析方法的推广，Polyakov 对二维非线性sigma 模型的有效作用量的计算被推广到包括那些非紫外发散且依赖于块状自旋选择的贡献。给出了决定经典完美作用量的背景场的一个解析近似，并找到了 1 环修正的近似值。这些结果应该对数值模拟有用。 显示英文摘要

摘要： Polyakov's calculation of the effective action for the 2d nonlinear sigma-Model is generalized by purely analytic means to include contributions which are not UV-divergent and which depend on the choice of block spin. An analytic approximation to the background field which determines the classical perfect action is given, and approximations to the 1-loop correction are found. The results should be useful for numerical simulations.