{ "id": "1808.00272", "version": "v1", "published": "2018-08-01T11:20:09.000Z", "updated": "2018-08-01T11:20:09.000Z", "title": "Automatic continuity of $\\aleph_1$-free groups", "authors": [ "Samuel M. Corson" ], "categories": [ "math.GR" ], "abstract": "We prove that groups for which every countable subgroup is free ($\\aleph_1$-free groups) are n-slender, cm-slender, and lcH-slender. In particular every homomorphism from a completely metrizable group to an $\\aleph_1$-free group has an open kernel. We also show that $\\aleph_1$-free abelian groups are lcH-slender, which is especially interesting in light of the fact that some $\\aleph_1$-free abelian groups are neither n- nor cm-slender. The strongly $\\aleph_1$-free abelian groups are shown to be n-, cm-, and lcH-slender. We also give a characterization of cm- and lcH-slender abelian groups.", "revisions": [ { "version": "v1", "updated": "2018-08-01T11:20:09.000Z" } ], "analyses": { "subjects": [ "20K20", "03E75", "22A05", "22B05" ], "keywords": [ "free group", "free abelian groups", "automatic continuity", "lch-slender abelian groups", "open kernel" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }