The tractability conjecture for reducts of finitely bounded homogeneous structures

From papers

Let A{\mathbb A} be a reduct of a finitely bounded homogeneous structure: it is obtained by forgetting some relations from a homogeneous structure, and the ambient structure is characterized among finite structures by forbidding embeddings of a finite set of finite structures. Let K3{\mathbb K}_3 denote the complete graph on three vertices, and let CSP(A)\operatorname{CSP}({\mathbb A}) be the problem of deciding whether a finite input structure admits a homomorphism to A{\mathbb A}.

The tractability conjecture. If A{\mathbb A} does not pp-construct K3{\mathbb K}_3, then CSP(A)\operatorname{CSP}({\mathbb A}) is polynomial-time solvable.

This is described as a wide-open generalization of the Feder–Vardi conjecture to reducts of finitely bounded homogeneous structures and is the subject of an active research program.

Progress summary

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

Sources & referencesView supporting material

Primary source

Santiago Guzmán-Pro and Barnaby Martin, “Restricted CSPs and F-free Digraph Algorithmics”, arXiv:2502.17596 (2025).

Solutions 0

No solutions have been posted yet.