摘要
The Metropolis Monte Carlo algorithm is applied to a classical O(2)model on nice tree and Bethe lattice.Finite-size scaling theory is applied to estimate the critical temperature.The results show that the continuous symmetry may not be spontaneously broken even if d_(f)≥d_(w)+1 where df and dw are the fractal dimension and the dimension of the random walk on the structure respectively or even if the random walk on the structure is transient.
基金
Supported in part by the Nonlinear Science Project of China and the State Education Committee Grant for doctor study。
