Archive for the ‘2013’ Category

Choongbum Lee (이중범), Ramsey numbers of cubes versus cliques

Wednesday, December 26th, 2012
Ramsey numbers of cubes versus cliques
Choongbum Lee (이중범)
Department of Mathematics, MIT, Cambridge, MA, USA
2013/01/04 Fri 4PM-5PM
The cube graph Qn is the skeleton of the n-dimensional cube. It is an n-regular graph on 2n vertices. The Ramsey number r(Qn, Ks) is the minimum N such that every graph of order N contains the cube graph Qn or an independent set of order s. Burr and Erdős in 1983 asked whether the simple lower bound r(Qn, Ks) ≥ (s-1)(2n -1)+1 is tight for s fixed and n sufficiently large. We make progress on this problem, obtaining the first upper bound which is within a constant factor of the lower bound.
Joint work w/ David Conlon, Jacob Fox, and Benny Sudakov