一句话:为 K、T、K4、GL、S4 的必要性片段建立双上下文自然演绎与模态 λ 演算,并给出范畴语义。
本文为正规模态逻辑 K、T、K4、GL 和 S4 的必要性片段给出一类自然演绎系统及其对应的模态 lambda 演算。这些系统采用双上下文风格,把假设分成模态与直觉主义两个区域,并说明其来源可追溯至相继式演算。作者研究其元理论,构造了合流且强规范化的归约关系,并证明这些演算在可证性意义上与通常的 Hilbert 系统一致。最后,他们考察了一种范畴语义,将模态算子解释为保持乘积的函子。该工作统一了模态逻辑的证明论、类型论与范畴语义视角。
We present natural deduction systems and associated modal lambda calculi for the necessity fragments of the normal modal logics K, T, K4, GL and S4. These systems are in the dual-context style: they feature two distinct zones of assumptions, one of which can be thought as modal, and the other as intuitionistic. We show that these calculi have their roots in in sequent calculi. We then investigate their metatheory, equip them with a confluent and strongly normalizing notion of reduction, and show that they coincide with the usual Hilbert systems up to provability. Finally, we investigate a categorical semantics which interprets the modality as a product-preserving functor.Comment: Full version of article previously presented at LICS 2017 (see arXiv:1602.04860v4 or doi: 10.1109/LICS.2017.8005089)