Planar graphs and Legendrian surfaces

Series
School of Mathematics Colloquium
Time
Friday, December 8, 2017 - 4:00pm for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Emmy Murphy – Northwestern University – http://www.math.northwestern.edu/~e_murphy/
Organizer
Mayya Zhilova
Associated to a planar cubic graph, there is a closed surface in R^5, as defined by Treumann and Zaslow. R^5 has a canonical geometry, called a contact structure, which is compatible with the surface. The data of how this surface interacts with the geometry recovers interesting data about the graph, notably its chromatic polynomial. This also connects with pseudo-holomorphic curve counts which have boundary on the surface, and by looking at the resulting differential graded algebra coming from symplectic field theory, we obtain new definitions of n-colorings which are strongly non-linear as compared to other known definitions. There are also relationships with SL_2 gauge theory, mathematical physics, symplectic flexibility, and holomorphic contact geometry. During the talk we'll explain the basic ideas behind the various fields above, and why these various concepts connect.