TY  - JOUR
A1  - Doerries, Timo J.
A1  - Chechkin, Aleksei V.
A1  - Metzler, Ralf
T1  - Apparent anomalous diffusion and non-Gaussian distributions in a simple mobile-immobile transport model with Poissonian switching
JF  - Interface : journal of the Royal Society
N2  - We analyse mobile-immobile transport of particles that switch between the mobile and immobile phases with finite rates. Despite this seemingly simple assumption of Poissonian switching, we unveil a rich transport dynamics including significant transient anomalous diffusion and non-Gaussian displacement distributions. Our discussion is based on experimental parameters for tau proteins in neuronal cells, but the results obtained here are expected to be of relevance for a broad class of processes in complex systems. Specifically, we obtain that, when the mean binding time is significantly longer than the mean mobile time, transient anomalous diffusion is observed at short and intermediate time scales, with a strong dependence on the fraction of initially mobile and immobile particles. We unveil a Laplace distribution of particle displacements at relevant intermediate time scales. For any initial fraction of mobile particles, the respective mean squared displacement (MSD) displays a plateau. Moreover, we demonstrate a short-time cubic time dependence of the MSD for immobile tracers when initially all particles are immobile.
KW  - diffusion
KW  - mobile-immobile model
KW  - tau proteins
Y1  - 2022
U6  - https://doi.org/10.1098/rsif.2022.0233
SN  - 1742-5689
SN  - 1742-5662
VL  - 19
IS  - 192
PB  - Royal Society
CY  - London
ER  -