{ "id": "1910.13836", "version": "v1", "published": "2019-10-30T13:21:57.000Z", "updated": "2019-10-30T13:21:57.000Z", "title": "Erratum to \"The integer cohomology algebra of toric arrangements\"", "authors": [ "Filippo Callegaro", "Emanuele Delucchi" ], "comment": "24 pages, 1 figure", "categories": [ "math.AT", "math.CO" ], "abstract": "We point out two errors in the paper \"The integer cohomology algebra of toric arrangements, Advances in Mathematics, Vol. 313, pp.~746--802, 2017. The main error concerns Theorem 4.2.17. In particular the Diagram (8) does not commute in general. This invalidates the description for the ring structure of $H^*(M(\\mathcal{A});\\mathbb{Z})$ given in Theorem A and B. Still, under some restrictive hypotesis on $\\mathcal{A}$ the results of Theorem 4.2.17 holds. We show a workaround to provide a description of the cohomology ring $H^*(M(\\mathcal{A});\\mathbb{Z})$ when $\\mathcal{A}$ is a real complexified toric arrangement. The second error concerns the proof Theorem 7.2.1. The claim holds, but the proof is incorrect. We refer to a counterexample for the argument given in the proof and we provide references for a correct proof.", "revisions": [ { "version": "v1", "updated": "2019-10-30T13:21:57.000Z" } ], "analyses": { "keywords": [ "integer cohomology algebra", "main error concerns theorem", "second error concerns", "real complexified toric arrangement", "proof theorem" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable" } } }