Hierarchical Combination of Unification Algorithms

Serdar Erbatur (1) , Deepak Kapur (2) , Andrew Marshall (3) , Paliath Narendran (4) , Christophe Ringeissen (5)

1 UNIVR | DI - Department of Computer Science [Verona]
2 The University of New Mexico [Albuquerque]
3 NRL - Naval Research Laboratory
4 University at Albany [SUNY]
5 CASSIS - Combination of approaches to the security of infinite states systems

A critical question in unification theory is how to obtain a unification algorithm for the combination of non-disjoint equational theories when there exists unification algorithms for the constituent theories. The problem is known to be difficult and can easily be seen to be undecidable in the general case. Therefore, previous work has focused on identifying specific conditions and methods in which the problem is decidable. We continue the investigation in this paper, building on previous combination results. We are able to develop a novel approach to the non-disjoint combination problem. The approach is based on a new set of restrictions and combination method such that if the restrictions are satisfied the method produces an algorithm for the unification problem in the union of non-disjoint equational theories.

Domaines: Logique en informatique [cs.LO]

Serdar Erbatur, Deepak Kapur, Andrew Marshall, Paliath Narendran, Christophe Ringeissen. Hierarchical Combination of Unification Algorithms. The 27th International Workshop on Unification (UNIF 2013), Jun 2013, Eindhoven, Netherlands. ⟨hal-00920509⟩