DEPARTMENT OF MATHEMATICAL SCIENCES

APPLIED AND COMPUTATIONAL MATHEMATICS SEMINAR

**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