Oct

20

2014

This talk concerns groups $J_4(m,k)$ and $J_6(m,k)$ defined by generators and relations. The presentations arose in the study of asphericity for \textit{relative group presentations}, where one considers the effects of adding new generators and new relations to a pre-existing group. \textit{Asphericity} means that the pre-existing group embeds in the new group and that all finite subgroups of the new group are present in the old one, up to conjugacy.

Oct

21

2014

Schubert calculus is a great source of beautiful identities which really ought to have bijective proofs. For instance, Macdonald (1991) proves, non-bijectively, an identity for a weighted sum over the reduced words for a permutation pi. I'll give a algorithmic bijective proof in the simplest case: when pi is a dominant permutation, the sum evaluates to l(pi)!

Oct

21

2014

We derive a large deviations principle for the trajectories generated by a class of ergodic Markov processes. Specifically, we work with M/M/∞ queueing processes. We study large deviations of these processes scaled equally in both space and time directions. Our main result is that the probabilities of long excursions originating at state 0 would converge to zero function with the rate proportional to the square of the scaling parameter. The rate function is expressed as an integral of a linear combination of trajectories.

Oct

24

2014

This talk serves as part II of a two-part elementary introduction to mathematical fluid mechanics. In this series of talks we will introduce and (at least partially) derive the Euler and Navier-Stokes equations modeling incompressible fluid flow in two and three dimensions. We will also discuss quantities of interest such as the velocity, pressure, vorticity, and particle trajectory map. For our discussion of inviscid flows modeled by the Euler equations, we will focus in particular on vortex motion, namely Kelvin's circulation theorem and the Helmholtz vortex theorems with applica

The F.A. Gilfillan Memorial Award for Distinguished Scholarship in Science for 2014 was awarded to Edward Waymire. The purpose of the award is to recognize distinguished scholarship in science by honoring a faculty member in the College of Science whose scholarship and scientific accomplishments have extended over a substantial period of time....

The Gladys Valley Award for Exemplary Administrative Support for 2014 was awarded to Deanne Wilcox. The purpose of this award is to recognize outstanding job performance and dedication by a College staff person to the individual's Department and to the College.