Problem of the Week
BUGCAT
Zassenhaus Conference
Hilton Memorial Lecture
BingAWM
Math Club
A shelling of a polytopal complex is an ordering of its maximal cells that proves that the polytopal complex is a ball or sphere. Not all polytopal balls and spheres have a shelling. I'll give some background on shellings and talk about Ziegler's construction of a nonshellable polytopal ball with only ten vertices.