Tempered Fractional Brownian Motion on Finite Intervals

Abstract

Diffusive transport in many complex systems features a crossover between anomalous diffusion at short times and normal diffusion at long times. This behavior can be mathematically modeled by cutting off (tempering) beyond a mesoscopic correlation time the power-law correlations between the increments of fractional Brownian motion. Here, we investigate such tempered fractional Brownian motion confined to a finite interval by reflecting walls. Specifically, we explore how the tempering of the long-time correlations affects the strong accumulation and depletion of particles near reflecting boundaries recently discovered for untempered fractional Brownian motion. We find that exponential tempering introduces a characteristic size for the accumulation and depletion zones but does not affect the functional form of the probability density close to the wall. In contrast, power-law tempering leads to more complex behavior that differs between the superdiffusive and subdiffusive cases.

Department(s)

Physics

Comments

This work was supported in part by a Cottrell SEED award from Research Corporation and by the National Science Foundation under Grant Nos. DMR-1828489 and OAC-1919789.

International Standard Serial Number (ISSN)

1434-6036; 1434-6028

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2021 EDP Sciences, All rights reserved.

Publication Date

14 Oct 2021

Share

 
COinS