Biological & Soft Matter Seminar: Doubly Stochastic Continuous Time Random Walk

Zoom: https://tau-ac-il.zoom.us/j/88904888353?pwd=dDIwaXRxSjlsVElkR0dXdTNPTGhnZz09

Abstarct:

In heterogeneous environments, such as biological cells, the diffusion of a molecule may not follow the expected normal diffusion, with its Gaussian probability distribution. The concept of diffusing diffusivity - a stochastic diffusion coefficient within the diffusion equation - was introduced to explain this phenomenology. We introduce a doubly stochastic version of the continuous time random walk (DSCTRW) in which we replace the all-familiar waiting times between jumps with a fluctuating jump rate. While this added layer of randomness gives rise to a rich phenomenology, the model remains fully tractable. We show that the DSCTRW provides an alternative pathway to Brownian yet non-Gaussian diffusion, which is also accompanied by exotic first-passage phenomena.