-
摘要: 我们研究了阻尼布朗粒子,在具有幂律长时相干C(t)~t-(01,12)的无规涨落力作用下的运动情况。我们发现它是作分形布朗运动,而不是作普通的布朗运动,而且,找出了分形布朗运动的有效Fokker-Planck方程,以及相应的精确解。于是第一次把长时相干效应和分形布朗运动建立了定量的联系。
-
关键词:
- 分形 /
- 布朗及分形布朗运动 /
- 扩散 /
- Fokker-Planck方程
Abstract: We present a comprehensive study of the motion of a damped Brownian particle undergoing a randomly fluctuating force with zero mean and a correlation function of a power-law time dependence, or C(t)~t-, 01, 12, instead of the Dirac delta-function. It is evident that this motion is fractional Brownian motion or fractal Brownian motion (fBm). The effective Fokker-Planck equation for fBm and its solution for fBm are presented. We have also established the quantitative relation of long-time correlation of power law time dependence to the fBm and anomalous diffusion.-
Key words:
- fractal /
- Brownian and fractal Brownian motion /
- diffusion /
- Fokker-Planck equation
-
Brown R. Phil Mag, 4(1828): 162. Einstein A. Investigations on the Theory of the Brownian Movement. Dover, New York, 1956. Mandelbrot B B, Van Ness J W. SIAM Review, 1968, 10: 422. Adler B J, Wainwright T E. Phys Rev Lett, 1967, 18: 988; Phys Rev A, 1970, 1: 18. Reichl L E. Phys Rev A, 1981, 24: 609. Aharony A. Scaling Phenomena in Disordered System. Edited by R Pynn, A Skjeltorp. Plenum Press, 1985: 289. Fox R F. Phys Rev A, 1986, 33: 467; Phys Rev A, 1986, 34: 4526. Wang K G, et al. Functional-Calculus Approach to Motion of a Damped Brownian Particle Evolving in a Long Time Correlation Fluctuating Force. Mandelbrot B B. The Fractal Geometry of Nature. New York: Freeman, 1982. Feder J. Fractals. New York and London: Plenum Press, 1988. Bouchaud J P, et al. Phys Rev Lett, 1990, 64: 2503. Voss R. Physica D, 1989, 38: 362.
点击查看大图
计量
- 文章访问数: 15929
- HTML全文浏览量: 2449
- PDF下载量: 1051