When: Sunday, December 6, 10am
Where: Schreiber 309
Speaker: Konstantin Golubev, Hebrew University
Title: Simplicial Complexes of High Chromatic Number
Ramanujan graphs, constructed by Lubotzky, Phillips and
Sarnak and known as the LPS graphs, form a family of explicitly
constructed graphs of high girth and high chromatic number. High
dimensional counterparts of the LPS graphs are the Ramanujan
Complexes, constructed by Lubotzky, Samuels and Vishne. They were
recently proved to have high chromatic number. In my talk, I will
concentrate on the combinatorial part of the proof of this result.
Based on a joint work with S.Evra, A.Lubotzky and O.Parzanchevski.