Susan Coppersmith
Professor of Physics
University of Chicago
 

What happens underneath your feet when you stand
on a beach?  This talk will show that the forces that
support your weight are distributed very differently
in sand than in a ``normal'' solid.  Forces much
larger than the mean occur, but are exponentially
rare.  These force inhomogeneities can be understood
using an exactly solvable statistical model, in
which the fluctuations in the force distribution
arise because of variations in the contact angles
and the constraints imposed by the force balance
on each bead in the pile.