Self-similarity of graphs

Choongbum Lee (이중범)

Department of Mathematics, UCLA, Los Angeles, USA

Department of Mathematics, UCLA, Los Angeles, USA

2012/7/4 Wed 4PM-5PM (Bldg. E6-1, Room 3433)

An old problem raised independently by Jacobson and Schönheim asks to determine the maximum s for which every graph with m edges contains a pair of edge-disjoint isomorphic subgraphs with s edges. We determine this maximum up to a constant factor and show that every m-edge graph contains a pair of edge-disjoint isomorphic subgraphs with at least c (m log m)2/3 edges for some absolute constant c, and find graphs where this estimate is off only by a multiplicative constant. Our results improve bounds of Erdős, Pach, and Pyber from 1987.

Joint work with Po-Shen Loh and Benny Sudakov.

Tags: 이중범