1. CJM 2011 (vol 65 pp. 3)
|Finitely Related Algebras in Congruence Distributive Varieties Have Near Unanimity Terms|
We show that every finite, finitely related algebra in a congruence distributive variety has a near unanimity term operation. As a consequence we solve the near unanimity problem for relational structures: it is decidable whether a given finite set of relations on a finite set admits a compatible near unanimity operation. This consequence also implies that it is decidable whether a given finite constraint language defines a constraint satisfaction problem of bounded strict width.
Keywords:congruence distributive variety, JÃ³nsson operations, near unanimity operation, finitely related algebra, constraint satisfaction problem