Society

Sam Qunell

Office 3957 Math Sciences Building
Office Hours Thursdays 1-2
E-Mail sdqunell at math .ucla .edu

Title Description
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.