  The Kuramoto-Sivashinsky equation was introduced as a simple 1-dimensional
model of instabilities in flames, but it turned out to mathematically
fascinating in its own right. One reason is that this equation is a simple
model of Galilean-invariant chaos with an arrow of time. Starting from random
initial conditions, manifestly time-asymmetric stripe-like patterns emerge. As
we move forward in time, it appears that these stripes are born and merge, but
do not die or split. We pose a precise conjecture to this effect, which
requires a precise definition of 'stripes'.
