Past Events

Abstract: Power’s 2-categorical pasting theorem, asserting that any pasting diagram in a 2-category has a unique composite, is at the basis of the 2-categorical graphical calculus, which is used extensively to develop the theory of 2-categories. In...

Knot Floer homology is a package of widely-used knot invariants constructed via pseudo-holomorphic curves. In this talk, we will restrict our attention to the knot Floer homology of a class of knots called satellite knots; understanding these...

Abstract: Recently, Mohar introduced a variant of the cops and robber game that is played on geodesic spaces. The game combines properties of pursuit-evasion games with the classical cops and robber game played on graphs. In the game, cops win if...

The Earth is warming and temperature isoclines are shifting. Empirical evidence suggests that shifting speeds of temperature isoclines are accelerating, are elevation- dependent, and that there is annualvariation around the expected location of the...

Abstract: Many results on hypoellipticity of second order operators rely on the assumption that the operator can be written as a sum of squares of vector fields (e.g. Hormander's bracket condition, and Christ's hypoellipticity theorem for infinitely...

Abstract: In the first part of this talk we will discuss several ways, how principal bundles over a manifold can be described. The main two of them are maps from the base manifold into the group’s classifying space and assignments of group elements...

Abstract: The number of independent sets in the hypercube {0,1}^d was estimated precisely by Korshunov and Sapozhenko in the 1980s and recently refined by Jenssen and Perkins. In this talk we will discuss new results on the number of independent sets...

Abstract: Given square matrices A_1, ..., A_d we can consider random products and the associated (top) Lyapunov exponent. We will consider two applications where the Lyapunov exponent plays an interesting role: firstly to barycentric subdivisions of...

The number of homomorphisms from a graph H to a graph G, denoted by hom(H;G), is the number of maps from V(H) to V(G) that yield a graph homomorphism, i.e., that map every edge of H to an edge of G. Given a fixed collection of finite simple graphs {H...