Exact Turán densities of hypergraphs

Determine the exact Turán density \(\pi(F)\) for arbitrary \(k\)-uniform hypergraphs \(F\) with \(k\geq 3\).

Background

The paper introduces the classical Turán density π(F)\pi(F) of a kk-uniform hypergraph as the asymptotic maximum edge density of an FF-free kk-graph. It explicitly identifies determining these values for general hypergraphs of uniformity at least three as a longstanding central problem in extremal combinatorics. This issue is presented as background motivating the study of the related codegree Turán density, rather than as a problem resolved by the paper.

References

Determining the value of~$\pi(F)$ for~$k$-graphs (with~$k\geq 3$) is one of the central open problems in combinatorics.

Infinitely many accumulation points of codegree Turán densities  (2502.13485 - Li et al., 19 Feb 2025) in Introduction