Theoretical Physics Colloquium
Two Centuries of Diffusion
by Prof. Sushanta Dattagupta (Visva-Bharati, Santiniketan)
Tuesday, June 18, 2013
from
to
(Asia/Kolkata)
at Colaba Campus ( AG69 )
at Colaba Campus ( AG69 )
Description |
This talk will cover more than two century-old history of Diffusion. What started from the French school of mathematical physicists, primarily Fourier and Laplace, who had introduced us to two distinct paradigms of diffusion -- physical and stochastic, the topic still occupies our space with its various ramifications. It is a subject that intertwines mathematics with observed phenomena, illustrated by Brown's findings of random zig-zag motion of pollen particles in a tube of water, kept at a fixed temperature .Thus, almost a century after Fourier and Laplace talked about physical and stochastic diffusion, Einstein unified the two disparate concepts through his path-breaking work on Brownian motion. Diffusion and co-operative interactions is another area of contemporary interest in the Chemistry and Physics of Materials and Biology. Thus, reaction-diffusion equations are at the core of pattern formation, morphogenesis and fractal colony growth of biological species. In the second part of the talk, we move to the subatomic arena when one asks what happens to an elementary particle such as an electron or a proton that undergoes diffusive motion. Their dynamic behavior, in interaction with their surroundings, leads to dissipative motion, which invariably necessitates the investigation of diffusion in the quantum domain. That study therefore directly impacts the contemporary subjects of dissipative tunneling, Landau diamagnetism, coherence-to-deceoherence transition, quantum information processes, and so on. |