Sponsored by Elizabethtown College, Franklin and Marshall College, Lebanon Valley College, and Millersville University
12 September David Lyons, Lebanon Valley College 3 October David Johnson, Lehigh University 7 November Josh Sabloff, Haverford College 5 December Vincent Coll, Lehigh University 6 February Lisa Traynor, Bryn Mawr College 6 March Zhigang Han, Millersville University 10 April Barbara Nimershiem, Franklin and Marshall CollegeTGTS meets at 4:30 p.m. on the first Friday of each month. The public is cordially invited to attend.
Date: 5 December 2014, 4:30pm Location: Hempfield High School, Room 213 Speaker: Vincent Coll, Lehigh University Title: The Homotopy Type of Seaweed Lie Algebras Abstract. An important (but difficult to compute) invariant of a Lie algebra is its index. In this talk we will show that for a certain class of Lie algebras (seaweeds), the index can be computed by counting the connected components of a remarkable planar graph (called a meander) associated with the seaweed algebra. The counting will require an understanding of the underlying homotopy type of the seaweed. We will pay particular attention to Frobenius algebras – those whose index is 0.