A nice demonstration of classical chiral symmetry breaking

I like concrete classroom demonstrations.

Andrew Boothroyd recently showed me a very elegant demonstration based on this paper
Spontaneous Chirality in Simple Systems
Galen T. Pickett, Mark Gross, and Hiroko Okuyama

It considers hard spheres confined to a cylinder. Different phases depending on the value of D, the ratio of the diameters of the cylinder and the spheres. The phase diagram is below.

Andrew has a nice demonstration using ping pong balls and a special transparent plastic cylinder that has the right diameter to produce a chiral phase. He shows it during a colloquium and sometimes even gets an applause!

I found a .ppt that has the nice pictures below.