Tight cycles and regular slices in dense hypergraphs

Allen, Peter, Böttcher, Julia, Cooley, Oliver and Mycroft, Richard (2016) Tight cycles and regular slices in dense hypergraphs. Journal of Combinatorial Theory, Series A . ISSN 0097-3165 (In Press)

PDF - Accepted Version Restricted to Repository staff only Download (595Kb)

• LSE expert's profile
• LSE expert's profile

Abstract

We study properties of random subcomplexes of partitions returned by (a suitable form of) the Strong Hypergraph Regularity Lemma, which we call regular slices. We argue that these subcomplexes capture many important structural properties of the original hypergraph. Accordingly we advocate their use in extremal hypergraph theory, and explain how they can lead to considerable simplifications in existing proofs in this field. We also use them for establishing the following two new results. Firstly, we prove a hypergraph extension of the Erd\H{o}s-Gallai Theorem: for every δ>0 every sufficiently large k-uniform hypergraph with at least (α+δ)(nk) edges contains a tight cycle of length αn for each α∈[0,1]. Secondly, we find (asymptotically) the minimum codegree requirement for a k-uniform k-partite hypergraph, each of whose parts has n vertices, to contain a tight cycle of length αkn, for each 0<α<1.

Item Type:	Article
Official URL:	http://www.journals.elsevier.com/journal-of-combin...
Additional Information:	© 2016 Elsevier Inc.
Library of Congress subject classification:	Q Science > QA Mathematics
Sets:	Departments > Mathematics
Date Deposited:	22 Jun 2016 15:14
URL:	http://eprints.lse.ac.uk/66980/

Actions (login required)

Record administration - authorised staff only