Noisy continuous time random walks

Abstract

Experimental studies of the diffusion of biomolecules in the environment of biological cells are routinely confronted with multiple sources of stochasticity, whose identification renders the detailed data analysis of single molecule trajectories quite intricate. Here we consider subdiffusive continuous time random walks, that represent a seminal model for the anomalous diffusion of tracer particles in complex environments. This motion is characterized by multiple trapping events with infinite mean sojourn time. In real physical situations, however, instead of the full immobilization predicted by the continuous time random walk model, the motion of the tracer particle shows additional jiggling, for instance, due to thermal agitation of the environment. We here present and analyze in detail an extension of the continuous time random walk model. Superimposing the multiple trapping behavior with additive Gaussian noise of variable strength, we demonstrate that the resulting process exhibits a rich variety of apparent dynamic regimes. In particular, such noisy continuous time random walks may appear ergodic while the naked continuous time random walk exhibits weak ergodicity breaking. Detailed knowledge of this behavior will be useful for the truthful physical analysis of experimentally observed subdiffusion.

16 pages, 13 figures

References in corpus (8)

• Anomalous transport in the crowded world of biological cells
• Random Time-Scale Invariant Diffusion and Transport Coefficients
• Probing microscopic origins of confined subdiffusion by first-passage observables
• Distribution of Time-Averaged Observables for Weak Ergodicity Breaking
• Subdiffusion and weak ergodicity breaking in the presence of a reactive boundary
• Occupation Time Statistics in the Quenched Trap Model
• Ergodic properties of continuous-time random walks: finite-size effects and ensemble dependences
• Universal fluctuations in subdiffusive transport

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