# Labeled Sequent Calculus for Orthologic

## Authors

• Tomoaki Kawano Tokyo Institute of Technology, School of Computing, Department of Mathematical and Computing Science

## Keywords:

quantum logic, sequent calculus, cut-elimination theorem, decidability, Kripke model

## Abstract

Orthologic (OL) is non-classical logic and has been studied as a part of quantumlogic. OL is based on an ortholattice and is also called minimal quantum logic. Sequent calculus is used as a tool for proof in logic and has been examinedfor several decades. Although there are many studies on sequent calculus forOL, these sequent calculi have some problems. In particular, they do not includeimplication connective and they are mostly incompatible with the cut-eliminationtheorem. In this paper, we introduce new labeled sequent calculus called LGOI, and show that this sequent calculus solve the above problems. It is alreadyknown that OL is decidable. We prove that decidability is preserved when theimplication connective is added to OL.

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2018-12-30

## How to Cite

Kawano, T. (2018). Labeled Sequent Calculus for Orthologic. Bulletin of the Section of Logic, 47(4), 217–232. https://doi.org/10.18778/0138-0680.47.4.01

Research Article