Submission date: 16 September 2014.

Abstract:

It is known that a countable ω-categorical structure interprets all finite structures primitively positively if and only if its polymorphism clone maps to the clone of projections on a two-element set via a continuous clone homomorphism. We investigate the relationship between the existence of a clone homomorphism to the projection clone, and the existence of such a homomorphism which is continuous and thus meets the above criterion.

Mathematics Subject Classification:

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Full text arXiv 1409.4601: pdf, ps.