Department of Physics
San Diego State University
San Diego, CA 92128
Research: Physics of - Polymeric and Biological - Soft Matter
Physics may be viewed as a collection of concepts. By combining these concepts we are able to understand a wide range of phenomena. My area of research, soft matter physics, is only a few decades old. Hence, unlike in older fields, many phenomena can not be explained in terms of established concepts. New ones must be developed.
To contribute to the formulation of these new concepts is the main purpose of my work. To this end, I perform computer simulations of yet unexplained phenomena. Insights obtained in these studies pave the way for more encompassing theories and constitutive equations with a wide range of applications.
A more specific objective is to enhance physical understanding of polymeric materials and biological systems driven far from equilibrium by a stress that is high relative to intrinsic relaxation times. This involves phenomena like yielding and phase slip, plasticity, crazing, shear banding, flow-induced ordering, memory, slip-stick flow, and racheting.
For polymeric materials, my current research efforts are focused on nonlinear transient phenomena in reversible polymeric gels and glassy thin films. We try to understand how macroscopic response is encoded in the structure and dynamics at the microscopic level. For biological systems, they are aimed at modeling mitochondrial structure, function, and dynamics as well as mucosal surfaces.In collaboration with biologist and mathematicins in SDSU's Viral Information Institute we study the dynamics of phage in a temporary cross-linked mucin network. The goal is to understand how the presence of mucus helps phages to hunt for bacteria and defend the human body. To this end, we are performing large scale MD/MC simulations of mucus using LAMMPS software. We then investigate the dynamics of model phage particles in the presence and absense of bacteria. These data are compared with similar studies performed in the lab. Here are some of our featured papers (more can be found below and a complete list on google scholar)
Topological changes at the gel transition of a reversible polymeric network Tensile forces and shape entropy explain observed crista structure in mitochondria
Physics 354, Modern Physics
Physics 608, Graduate Classical Mechanics
Physics and Chemistry 538, Polymer Science (offered Spring 2016)
Physics 606 Graduate Statistical Mechanics
Info for students interested in research
J. Barr et al. Subdiffusive motion of bacteriaphage in muscosal surfaces increases the frequency of bacterial encounters PNAS (2015)
M. Wilson, A. Rabinovitch, and A. Baljon Computational Study of the Structure and Rheological Properties of Self-Associating Polymer Networks Macromolecules 48, pp 7-12 (2015)
J. Billen, M. Wilson, and A. Baljon Shearbanding in Simulated Telechelic Polymers Chem. Phys. 406, pp 7-12 (2015)
COMPUTATIONAL SCIENCE RESEARCH CENTER
this page last updated: 7/31/15