Date & Time: Friday, December 24, 2010 at 3 pm
Venue: Ramanujan Hall
Title: On arrangements of complex hyperplanes whose fundamental group is a direct product of free groups.
Speaker: Prof. Kwai-Man Fan, National Chung-Cheng University, Taiwan
Abstract: We shall discuss a theorem and a conjecture on the fundamental group of the complement of a union of complex hyperplane that was given by myself in 1997, and the solution of the conjecture given by Meital Eliyahu, Eran Liberman, Malka Schaps, Mina Teicher in a joint paper that was published this year. Now we know exactly when this fundamental group is a direct product of free groups. We shall also discuss a very recent result by K. Williams on the topology of the complement. The results given in this lecture follows from an accumulation of works by many authors in the past 30 years.