Seminar

Title: Using eigenvalues to bound the independence number of a graph

Abstract:

Finding a maximum independent set (or clique) in an arbitrary graph has been shown to be NP-hard.  As any independent set gives a lower bound on the independence number, determining an upper bound is usually more useful. 

Title: Periodic Vertices in Graphs

Abstract:

If $X$ is a graph with adjacency matrix $A$, then any question about the continuous quantum walk on $X$ is a question about the entries of the unitary matrices \[U(t) = \exp(itA)\]

Two pertinent questions are:

Title: Geometric drawings of graphs (Part I)

Abstract:

This is the first of two talks about drawings of graphs that arise from geometry.

Part I: Understanding rectilinear drawings.

Title: Cospectral graphs, cospectral complements

Abstract: