Minimum Semidefinite Rank of Graphs by Jonathon Beagley Minimum semidefinite rank (MSR) of a graph, G, is defined to be min{rank(A), for all A in P(G)}, where P(G) is the set of PSD matrices with corresponding graph G. New results in this topic will be described, and a catalogue of graphs with known MSRs will be discussed. These results, include a new proof of the vertex sum of two graphs, and a new classification of all graphs with msr(G) =v(G)  2. This last result is done independently of Holst's classification in 2003.
Silver Cubes by Kevin Ventullo Let I be a maximum independent set in G, the cartesian product of three copies of the complete graph on n vertices. A silver cube is a coloring (using 3n2 colors) of all vertices in G such that the closed neighborhood of every vertex in I contains every color precisely once. The problem can be restated visually in a somewhat friendlier way, bearing a slight resemblance to a sudoku puzzle. It is an open question whether any silver cubes exist besides those where n = (2^p)(3^q)(5^s)(7^t). The extension to factor 7 was discovered this past summer using a method that will be presented in the talk.
