The block sets conjecture

From papers

Let [m]={1,,m}[m]=\{1,\ldots,m\}, and let a template over [m][m] be a non-decreasing word T[m]lT\in[m]^l for some positive integer ll. A block set with template TT in [m]n[m]^n is formed by choosing pairwise disjoint blocks I1,,Il[n]I_1,\ldots,I_l\subset[n] of a common size dd, fixing the remaining coordinates, and allowing the coordinates on the blocks to realize every permutation of the letters of TT.

Block sets conjecture. For every pair of positive integers mm and kk and every template TT over [m][m], there exist positive integers nn and dd such that every kk-colouring of [m]n[m]^n contains a monochromatic block set of degree dd with template TT.

The conjecture is a purely combinatorial statement that implies every subtransitive set is Ramsey. It is also described as an abstract version of the conjecture that all transitive sets are Ramsey, and remains open.

Progress summary

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Sources & referencesView supporting material

Primary source

Maria-Romina Ivan, Imre Leader and Mark Walters, “Generalised Prisms and Euclidean Ramsey Theory”, arXiv:2606.13472 (2026).

Additional references

2 papers in this index state this conjecture (2024–2026). The statement above is taken from the most recent of them; the others are arXiv:2406.01459.

Solutions 0

No solutions have been posted yet.