Some problems not definable using structure homomorphisms

Madelaine, F.R.; Stewart, I.A.

Abstract

We exhibit some problems definable in Feder and Vardi's logic MMSNP that are not in the class CSP of constraint satisfaction problems. Whilst some of these problems have previously been shown to be in MMSNP (that is, definable in MMSNP) but not in CSP, existing proofs are probabilistic in nature. We provide explicit combinatorial constructions to prove that these problems are not in CSP and we use these constructions to exhibit yet more problems in MMSNP that are not in CSP.

Citation

Madelaine, F., & Stewart, I. (2003). Some problems not definable using structure homomorphisms. Ars combinatoria, 67, 153-159

• Journal Article Type: Article
• Publication Date: Apr 1, 2003
• Deposit Date: Jun 29, 2009
• Journal: Ars combinatoria.
• Print ISSN: 0381-7032
• Publisher: Charles Babbage Research Centre
• Peer Reviewed: Peer Reviewed
• Volume: 67
• Pages: 153-159
• Keywords: Constraint satisfaction, CSP, MMSNP.
• Public URL: https://durham-repository.worktribe.com/output/1597749
• Publisher URL: http://bkocay.cs.umanitoba.ca/arscombinatoria/vol67.html