English

Bandwidth theorem for random graphs

Combinatorics 2015-03-17 v2

Abstract

A graph GG is said to have \textit{bandwidth} at most bb, if there exists a labeling of the vertices by 1,2,...,n1,2,..., n, so that ijb|i - j| \leq b whenever {i,j}\{i,j\} is an edge of GG. Recently, B\"{o}ttcher, Schacht, and Taraz verified a conjecture of Bollob\'{a}s and Koml\'{o}s which says that for every positive r,Δ,γr,\Delta,\gamma, there exists β\beta such that if HH is an nn-vertex rr-chromatic graph with maximum degree at most Δ\Delta which has bandwidth at most βn\beta n, then any graph GG on nn vertices with minimum degree at least (11/r+γ)n(1 - 1/r + \gamma)n contains a copy of HH for large enough nn. In this paper, we extend this theorem to dense random graphs. For bipartite HH, this answers an open question of B\"{o}ttcher, Kohayakawa, and Taraz. It appears that for non-bipartite HH the direct extension is not possible, and one needs in addition that some vertices of HH have independent neighborhoods. We also obtain an asymptotically tight bound for the maximum number of vertex disjoint copies of a fixed rr-chromatic graph H0H_0 which one can find in a spanning subgraph of G(n,p)G(n,p) with minimum degree (11/r+γ)np(1-1/r + \gamma)np.

Keywords

Cite

@article{arxiv.1005.1947,
  title  = {Bandwidth theorem for random graphs},
  author = {Hao Huang and Choongbum Lee and Benny Sudakov},
  journal= {arXiv preprint arXiv:1005.1947},
  year   = {2015}
}

Comments

29 pages, 3 figures

R2 v1 2026-06-21T15:21:29.122Z