Partition and almost disjoint properties of combinatorially rich sets in uncountable semigroups
Determine whether, for an infinite semigroup S of cardinality κ and a combinatorially rich subset A of S, the set A contains κ pairwise disjoint combinatorially rich subsets and, whenever κ contains λ almost disjoint subsets, contains λ almost disjoint combinatorially rich subsets.
References
We do not know whether an analogous result of Theorem 3.2 holds in uncountable semigroups, so we close this section with this question. Question 3.3. If (S, +) is an infinite semigroup of size κ and A is combinatorially rich in S, then does A contain κ pairwise disjoint combinatorially rich subsets? Moreover, if κ contains λ almost disjoint subsets, then does A contain λ almost disjoint combinatorially rich subsets?
— On partition and almost disjoint properties of combinatorial notions
(2501.11334 - Zhang, 20 Jan 2025) in Question 3.3, Section 3, p. 13