English

Finite Model Theory of the Triguarded Fragment and Related Logics

Logic in Computer Science 2021-01-26 v2 Artificial Intelligence Computational Complexity Logic

Abstract

The Triguarded Fragment (TGF) is among the most expressive decidable fragments of first-order logic, subsuming both its two-variable and guarded fragments without equality. We show that the TGF has the finite model property (providing a tight doubly exponential bound on the model size) and hence finite satisfiability coincides with satisfiability known to be N2ExpTime-complete. Using similar constructions, we also establish 2ExpTime-completeness for finite satisfiability of the constant-free (tri)guarded fragment with transitive guards.

Keywords

Cite

@article{arxiv.2101.08377,
  title  = {Finite Model Theory of the Triguarded Fragment and Related Logics},
  author = {Emanuel Kieroński and Sebastian Rudolph},
  journal= {arXiv preprint arXiv:2101.08377},
  year   = {2021}
}