Establish stability for the modified Erdős–Frankl–Pach conjecture

Prove that, if the modified uniform Erdős–Frankl–Pach conjecture holds and a qualifying family \(\mathcal{F}\) is not a star, then \(|\mathcal{F}|\leq\binom{n-1}{d}-Cn^{d-s}\) for some positive constant \(C\).

Background

The paper proves a strong stability theorem in the case s=1s=1, while showing that an analogous statement for s=ds=d with a substantially larger gap cannot hold in that form. It therefore proposes the scale ndsn^{d-s} as the appropriate general stability deficit for the unresolved general conjecture.

References

Therefore, we conjecture that if~\cref{conj:TrueGeneralization} holds, there might also exist a similar stability result. Specifically, for general s, if \mathcal{F} is not a star, then its size would not exceed \binom{n-1}{d} - Cn{d-s} for some positive constant $C$.

Uniform set systems with small VC-dimension  (2501.13850 - Chao et al., 23 Jan 2025) in Section 6, Concluding remarks