Memory effects in fractional Brownian motion with Hurst exponent H<1/3

Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Aug;82(2 Pt 1):020102. doi: 10.1103/PhysRevE.82.020102. Epub 2010 Aug 27.

Abstract

We study the regression to the origin of a walker driven by dynamically generated fractional Brownian motion (FBM) and we prove that when the FBM scaling, i.e., the Hurst exponent H<1/3 , the emerging inverse power law is characterized by a power index that is a compelling signature of the infinitely extended memory of the system. Strong memory effects leads to the relation H=θ/2 between the Hurst exponent and the persistent exponent θ , which is different from the widely used relation H=1-θ . The latter is valid for 1/3<H<1 and is known to be compatible with the renewal assumption.