{ "id": "2003.13207", "version": "v1", "published": "2020-03-30T03:56:02.000Z", "updated": "2020-03-30T03:56:02.000Z", "title": "Two remarks on proof theory of first-order arithmetic", "authors": [ "Toshiyasu Arai" ], "categories": [ "math.LO" ], "abstract": "In this note let us give two remarks on proof-theory of PA. First a derivability relation is introduced to bound witnesses for provable $\\Sigma_{1}$-formulas in PA. Second Paris-Harrington's proof for their independence result is reformulated to show a `consistency' proof of PA based on a combinatorial principle.", "revisions": [ { "version": "v1", "updated": "2020-03-30T03:56:02.000Z" } ], "analyses": { "subjects": [ "03F30" ], "keywords": [ "proof theory", "first-order arithmetic", "second paris-harringtons proof", "bound witnesses", "combinatorial principle" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }