Discrete CATS Seminar

U N I V E R S I T Y   O F   K E N T U C K Y
DISCRETE CATS SEMINAR
WHERE CATS = COMBINATORICS, ALGEBRA, TOPOLOGY & STATISTICS!

845 PATTERSON OFFICE TOWER
FALL 2009



Matt Zeckner

"Neighborhood Complex of Stable Kneser Graphs"

Matt Zeckner
University of Kentucky



Qualifying Exam
Monday, August 31, 2009
2:00 pm, 745 Patterson Office Tower


Abstract:

In 2003, A. Björner and M. De Longueville showed that the neighborhood complexes of a family of vertex critical subgraphs of Kneser graphs, known as the stable Kneser graphs introduced by A. Schrijver, are spheres up to homotopy. We shall present their proof which uses various topological methods including the Gluing lemma, Multicone lemma, and Nerve lemma.