Martingale drift of Langevin dynamics and classical canonical spin statistics
arXiv:2305.04976 · doi:10.1103/PhysRevE.109.014106
Abstract
The martingale characterizes a kind of fairness or unbiased nature of the stochastic process which is associated with another stochastic process. If evolves according to the Langevin equation whose mean drift is as function of and that as induced stochastic process is martingale in turn associated with the former process, then we show that the amplitude of is the Langevin function, which is originally the canonical response of a single classical Heisenberg spin under static field. Furthermore, the asymptotic limit of obeys the ensemble statistics of such Heisenberg spin.
7 pages, 3 figures, submitted