Sidney R. Nagel
Louis Block Professor, Physics
University of Chicago

Many complex phenomena are so familiar that we forget to ask
whether or not they are understood.  In this lecture, I will discuss
several familiar cases of effects that are so ubiquitous that we
hardly realize that they defy our normal intuition about why they
occur.  The examples of poorly understood classical physics that I
will choose can all be viewed at a breakfast table: the anomalous
flow of granular material, the long messy tendrils left by honey
spooned from one dish to another and the pesky rings deposited
by spilled coffee on a table after the liquid evaporates.  These are
all non-linear hydrodynamic phenomena which not only are of
technological importance but can also lead the inquisitive into
new realms of physics.