Society

Sam Qunell

Office 6146 Math Sciences Building
Office Hours Mondays 4-5 PM
E-Mail sdqunell at math .ucla .edu

Title Description
2-Categorical affine symmetries of quantum enveloping algebras We produce 2-representations of the positive part of affine quantum enveloping algebras on their finite-dimensional counterparts in type A_n. These 2-representations naturally extend the right-multiplication 2-representation of U_q^+(sl_(n+1)) on itself and are closely related to evaluation morphisms of quantum groups. We expect that our 2-representation exists in all simple types and show that the corresponding 1-representation exists in type D_4.
Characterization of saturated graphs related to pairs of disjoint matchings Continuation of the paper below. We first show that graph decompositions into paths and even cycles provide a new way to study this ratio. We then use this technique to characterize the graphs achieving ratio 1 among all graphs that can be covered by a certain choice of a maximum matching and maximum disjoint matchings. Published in the Illinois Journal of Mathematics.
Pairs of disjoint matchings and related classes of graphs We study the ratio, in a finite graph, of the sizes of the largest matching in any pair of disjoint matchings with the maximum total number of edges and the largest possible matching. Previously, it was shown that this ratio is between 4/5 and 1, and the class of graphs achieving 4/5 was completely characterized. Here, we show that any rational number between 4/5 and 1 can be achieved by a connected graph. Furthermore, we prove that every graph with ratio less than 1 must admit special subgraphs. Part of an undergraduate research project while I was at UIUC.
Magnetic Ergostars, Jet Formation, and Gamma-Ray Bursts: Ergoregions versus Horizons We perform the first fully general relativistic, magnetohydrodynamic simulations of dynamically stable hypermaassive neutron stars with and without ergoregions to asses the impact of ergoregions on launching magnetically-driven outflows. Part of an undergraduate research project (in the physics department) while I was at UIUC. Published in Physical Review D.