English

Norm hypergraphs

Combinatorics 2021-01-05 v1

Abstract

We introduce a high uniformity generalization of the so-called (projective) norm graphs of Alon, Koll\'ar, R\'onyai, and Szab\'o, and use it to show that exd(n,Ks1,,sd(d))=Θ(nd1s1sd1)\operatorname{ex}_{d}(n,K_{s_{1},\ldots,s_{d}}^{(d)}) = \Theta\left(n^{d - \frac{1}{s_{1}\ldots s_{d-1}}}\right) holds for all integers s1,,sd2s_{1},\ldots,s_{d} \geq 2 such that sd((d1)(s1sd11))!+1s_{d} \geq \left((d-1)(s_{1}\ldots s_{d-1}-1)\right)!+1. This improves upon a recent result of Ma, Yuan and Zhang, and thus settles (many) new cases of a conjecture of Mubayi.

Cite

@article{arxiv.2101.00715,
  title  = {Norm hypergraphs},
  author = {Cosmin Pohoata and Dmitriy Zakharov},
  journal= {arXiv preprint arXiv:2101.00715},
  year   = {2021}
}