Who told you that diffusion was a dead field of investigation? Diffusing diffusivity, anomalous diffusion, aging and other surprises.

Diffusion, or Brownian motion, is of great importance in various scientific disciplines including materials science, analytical chemistry, environmental sciences, social sciences, finance, and biophysics. The theory explaining the process is rather old, and includes the famous 1905 Einstein paper, Brown’s discovery of moving pollen particles (1827), Fick’s law (1855), and the like. Does it mean that the field is dead or dying? NO! It has just become “anomalous”! The field is actually booming. Of great interest recently is diffusion in random or disordered systems (real systems are not often as simple as the ones you see in your textbook). What if the diffusion coefficient itself is diffusing? What about non-Gaussian distributions that coexist with normal diffusion – is it even possible? Can systems age such that results depend on the observation time or the sampling process? What about ergodicity? Can we use random processes to drive the motion of particles in non-random directions? In this presentation, I will introduce several new concepts and results that have recently made the field “cool” again. Theory, simulations and experiments all contribute to our new understanding of these processes, with lots of examples coming from very interdisciplinary groups and research projects.

In 1984 after receiving a Ph.D. from the Université de Sherbrooke, Gary Slater worked for six years at Xerox Research Centre of Canada in Mississauga. In 1990, he joined the Department of Physics at the University of Ottawa, where he was named Professor in 1996. From July 1997 to August 2018, Gary Slater was Vice-dean of two different Faculties, then Dean and finally Associate Vice-President, all the University of Ottawa. Dr. Slater is a specialist in the physics of polymers and macromolecules. He is also interested in electrophoresis (a technique for separating biomolecules such as DNA and proteins), microfluidics, nanofluidics, computer simulations and the applications of the theory of diffusion in biophysics. Dr. Slater is a Fellow of both the American Physical Society and the Royal Society of Canada.