Speaker:Andrew Bernoff, Harvey Mudd College
Title: Langmuir Layers: Exploring a (nearly) Two-dimensional Fluid Experiment

Abstract: A Langmuir Layer is a molecularly thin layer of a polymer, lipid or liquid crystal on the surface of another fluid. In this (nearly) two-dimensional layer, we can observe bubbles of a fluid phase that even when stretched or highly contorted always appear to return to a circular shape. The force driving these evolutions is line tension, a two-dimensional analog of surface tension. We report on a combined experimental, theoretical, and numerical study of Langmuir layers, and show how we can deduce the strength of the line tension in the system by comparing theory and experiment. As time permits we will also report on some other phenomena observed in Langmuir systems, including collapse of gas phase bubbles, co-existence of three or more fluid phases, and formation of dogbone and labyrinth patterns due to dipolar repulsion in the layer.

Time: Friday, April 15, 2011, 3:30-4:30 p.m. (NOTE: Special Time: Joint with Math Colloquium)

Place: Science and Tech I, Room 242

Department of Mathematical Sciences
George Mason University
4400 University Drive, MS 3F2
Fairfax, VA 22030-4444
http://math.gmu.edu/
Tel. 703-993-1460, Fax. 703-993-1491