Ruzsa's discrete Brunn–Minkowski conjecture

Let kNk\in\mathbb{N} and let ϵ\epsilon be positive. For finite sets A,BZkA,B\subset\mathbb{Z}^k, say that BB is not covered by nn parallel hyperplanes when no collection of nn parallel hyperplanes contains BB. Ruzsa's discrete Brunn–Minkowski conjecture. For every kNk\in\mathbb{N} and ϵ\epsilon there exists nk,ϵn_{k,\epsilon} such that, whenever A,BZkA,B\subset\mathbb{Z}^k and BB is not covered by nk,ϵn_{k,\epsilon} parallel hyperplanes, one has

A+B1/kA1/k+(1ϵ)B1/k.|A+B|^{1/k}\geq |A|^{1/k}+(1-\epsilon)|B|^{1/k}.

This conjecture seeks a discrete analogue of the Brunn–Minkowski inequality under the natural minimal non-degeneracy assumption proposed by Ruzsa. Earlier results obtain the desired asymptotic bound either under stronger density assumptions or give substantially weaker bounds under full-dimensionality assumptions.

Sources & referencesView supporting material

Primary source

Peter van Hintum, Peter Keevash and Marius Tiba, “On Ruzsa's discrete Brunn-Minkowski conjecture”, arXiv:2306.13225 (2023).

Additional references

2 papers in this index state this conjecture (2023). The statement above is taken from the most recent of them; the others are arXiv:2304.01189.

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.