{ "id": "1804.06130", "version": "v1", "published": "2018-04-17T09:38:43.000Z", "updated": "2018-04-17T09:38:43.000Z", "title": "Ruitenburg's Theorem via Duality and Bounded Bisimulations", "authors": [ "Luigi Santocanale", "Silvio Ghilardi" ], "categories": [ "math.LO", "cs.LO" ], "abstract": "For a given intuitionistic propositional formula A and a propositional variable x occurring in it, define the infinite sequence of formulae { A \\_i | i$\\ge$1} by letting A\\_1 be A and A\\_{i+1} be A(A\\_i/x). Ruitenburg's Theorem [8] says that the sequence { A \\_i } (modulo logical equivalence) is ultimately periodic with period 2, i.e. there is N $\\ge$ 0 such that A N+2 $\\leftrightarrow$ A N is provable in intuitionistic propositional calculus. We give a semantic proof of this theorem, using duality techniques and bounded bisimulations ranks.", "revisions": [ { "version": "v1", "updated": "2018-04-17T09:38:43.000Z" } ], "analyses": { "keywords": [ "ruitenburgs theorem", "intuitionistic propositional formula", "intuitionistic propositional calculus", "infinite sequence", "modulo logical equivalence" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }