Do small or slender automorphisms force mixed identities?
Determine whether, for an ω‑categorical relational structure (X,R), the existence of a non‑trivial small automorphism (i.e., an automorphism fixing an infinite definable subset pointwise) or a non‑trivial slender automorphism (i.e., an automorphism c for which there exist a finite set Y and an infinite definable set Z ⊆ X with Z ⊆ {x ∈ X | x.c ∈ acl(Y ∪ {x})}) implies that the automorphism group Aut(X,R) satisfies a mixed identity.
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References
Remark 2.2.5. Despite numerous examples in Section 3 we do not know whether the existence of non-trivial small or slender automorphisms for some ω-categorical relational structure (X,R) implies the existence of a mixed identity for Aut(X,R).
— Mixed identities for oligomorphic automorphism groups
(2401.09205 - Bodirsky et al., 17 Jan 2024) in Remark 2.2.5