Divisors on graphs, connected flags, and syzygies

Series
Combinatorics Seminar
Time
Friday, October 12, 2012 - 3:05pm for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Farbod Shokrieh – Georgia Tech
Organizer
Prasad Tetali
Associated to every finite graph G there is a canonical ideal which encodes the linear equivalences of divisors on G. We study this ideal and its associated initial ideal. We give an explicit description of their syzygy modules and the Betti numbers in terms of the "connected flags" of G. This resolves open questions posed by Postnikov-Shapiro, Perkinson-Perlmen-Wilmes, and Manjunath-Sturmfels. No prior knowledge in advanced commutative algebra will be assumed. This is a joint work with Fatemeh Mohammadi.