|Date: Friday, May 04, 2012
Location: B 844 East Hall (4:00 PM to 5:00 PM)
Title: Cubical Small-cancellation theory
Abstract: An ordinary presentation < a_1, a_2,â�¦ | W_1, W_2, â�¦ > Â can be thought of as the quotient of the fundamental group of a graphobtained by killing the normal subgroup generated by immersed circles. We examine â��cubical presentationsâ��Â < X | Y_1, Y_2, â�¦ > where X is an arbitrary nonpositively curved cube complex, and each Y_i is a cube complex mapping to X by a local isometry. Classical small-cancellation theory enables one to understand a presentation when the overlap pieces between relators are quite small. We describe a faithful generalization of this to obtain a small-cancellation theory for cubical presentations.
Speaker: Dani Wise