**Thursday, October 26/10:45 AM**
**Retiring President's Address**

## Free Boundary Problems

In the first part of this address, the speaker will survey the basic theory of free boundary problems, and in the second part discuss his recent research in thermonuclear plasma and in coating flows. For the plasma problem the free boundary conditions include a jump of the square of u where u is harmonic from one side of the boundary and subharmonic from the other side. For the viscous flow problem the free boundary conditions involve the continuity of the normal stress and zero shear stress. The speaker will discuss existence results and properties of the free boundary.
**Avner Friedman**

Institute for Mathematics and Its Applications

University of Minnesota Minneapolis

7/21/95