{ "id": "2211.13749", "version": "v1", "published": "2022-11-24T18:30:35.000Z", "updated": "2022-11-24T18:30:35.000Z", "title": "On projections of the tails of a power", "authors": [ "Samuel M. Corson", "Saharon Shelah" ], "categories": [ "math.LO", "math.GR", "math.RA" ], "abstract": "Let $\\kappa$ be an inaccessible cardinal, $\\mathfrak{U}$ be a universal algebra, and $\\sim$ be the equivalence relation on $\\mathfrak{U}^{\\kappa}$ of eventual equality. From mild assumptions on $\\kappa$ we give general constructions of $\\mathcal{E} \\in End(\\mathfrak{U}^{\\kappa}/\\sim)$ satisfying $\\mathcal{E} \\circ \\mathcal{E} = \\mathcal{E}$ which do not descend from $\\Delta \\in End(\\mathfrak{U}^{\\kappa})$ having small strong supports. As an application there exists an $\\mathcal{E} \\in End(\\mathbb{Z}^{\\kappa}/\\sim)$ which does not come from a $\\Delta \\in End(\\mathbb{Z}^{\\kappa})$.", "revisions": [ { "version": "v1", "updated": "2022-11-24T18:30:35.000Z" } ], "analyses": { "subjects": [ "20A15", "03E55", "03G05" ], "keywords": [ "projections", "small strong supports", "equivalence relation", "eventual equality", "universal algebra" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }