Characterizing the NP-PSPACE Gap in the Satisfiability Problem for Modal Logic
Cached
Download Links
by
Joseph Y. Halpern
,
Leondro Chaves Rêgo
| Citations: | 4 - 1 self |
BibTeX
@MISC{Halpern_characterizingthe,
author = {Joseph Y. Halpern and Leondro Chaves Rêgo},
title = {Characterizing the NP-PSPACE Gap in the Satisfiability Problem for Modal Logic},
year = {}
}
Bookmark
 |
 |
 |
 |
 |
 |
OpenURL
Abstract
There has been a great deal of work on characterizing the complexity of the satisfiability and validity problem for modal logics. In particular, Ladner showed that the satisfiability problem for all logics between K and S4 is PSPACE-hard, while for S5 it is NP-complete. We show that it is negative introspection, the axiom ~ Kp) K~Kp, thatcauses the gap: if we add this axiom to any modal logic between K and S4, then the satisfiability problem becomes NP-complete. Indeed, the satisfiability problem is NP-complete for
