title: Stochastic fractal behavior in concentration fluctuation and fluorescence correlation spectroscopy.
abstract: Fluctuations in the concentration of Brownian particles in one and two dimensions, or any reasonable measurement of the concentration such as in fluorescence correlation spectroscopy, is shown to be a stochastic fractal with a long tail. Being singular at omega = 0, the power spectrum of the fluctuation S(omega) approximately omega-1/2 for diffusion in one dimension, approximately log omega in two dimensions, but non-singular in three dimensions. This discovery provides one simple physical mechanism for possible long-memory fractal behavior, and its implications to various biological processes are discussed.
authors.affiliation: Department of Applied Mathematics, University of Washington, Seattle 98195, USA.
authors.forename: H
authors.initials: H
authors.lastname: Qian
authors.forename: G M
authors.initials: GM
authors.lastname: Raymond
authors.forename: J B
authors.initials: JB
authors.lastname: Bassingthwaighte
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004058:Diffusion; D017709:Fractals; D008962:Models, Theoretical; D009038:Motion; D013050:Spectrometry, Fluorescence; D013269:Stochastic Processes