English

Spanning spheres in Dirac hypergraphs

Combinatorics 2025-06-17 v2

Abstract

We show that a kk-uniform hypergraph on nn vertices has a spanning subgraph homeomorphic to the (k1)(k - 1)-dimensional sphere provided that HH has no isolated vertices and each set of k1k - 1 vertices supported by an edge is contained in at least n/2+o(n)n/2 + o(n) edges. This gives a topological extension of Dirac's theorem and asymptotically confirms a conjecture of Georgakopoulos, Haslegrave, Montgomery, and Narayanan. Unlike typical results in the area, our proof does not rely on the Absorption Method, the Regularity Lemma or the Blow-up Lemma. Instead, we use a recently introduced framework that is based on covering the vertex set of the host graph with a family of complete blow-ups.

Keywords

Cite

@article{arxiv.2407.06275,
  title  = {Spanning spheres in Dirac hypergraphs},
  author = {Freddie Illingworth and Richard Lang and Alp Müyesser and Olaf Parczyk and Amedeo Sgueglia},
  journal= {arXiv preprint arXiv:2407.06275},
  year   = {2025}
}

Comments

28 pages; appendix added; final version

R2 v1 2026-06-28T17:33:25.045Z