English

Proof-theoretic aspects of NL$\lambda$

Computation and Language 2020-10-26 v1

Abstract

We present a proof-theoretic analysis of the logic NLλ\lambda (Barker \& Shan 2014, Barker 2019). We notably introduce a novel calculus of proof nets and prove it is sound and complete with respect to the sequent calculus for the logic. We study decidability and complexity of the logic using this new calculus, proving a new upper bound for complexity of the logic (showing it is in NP) and a new lower bound for the class of formal language generated by the formalism (mildly context-sensitive languages extended with a permutation closure operation). Finally, thanks to this new calculus, we present a novel comparison between NLλ\lambda and the hybrid type-logical grammars of Kubota \& Levine (2020). We show there is an unexpected convergence of the natural language analyses proposed in the two formalism. In addition to studying the proof-theoretic properties of NLλ\lambda, we greatly extends its linguistic coverage.

Keywords

Cite

@article{arxiv.2010.12223,
  title  = {Proof-theoretic aspects of NL$\lambda$},
  author = {Richard Moot},
  journal= {arXiv preprint arXiv:2010.12223},
  year   = {2020}
}
R2 v1 2026-06-23T19:34:50.919Z