{ "id": "1909.06906", "version": "v1", "published": "2019-09-15T23:22:29.000Z", "updated": "2019-09-15T23:22:29.000Z", "title": "Scattered products in fundamental groupoids", "authors": [ "Jeremy Brazas" ], "categories": [ "math.AT" ], "abstract": "Infinitary operations, such as products indexed by countably infinite linear orders, arise naturally in the context of fundamental groups and groupoids. We prove that the well-definedness of products indexed by a scattered linear order in the fundamental groupoid of a first countable space is equivalent to the homotopically Hausdorff property. To prove this characterization, we employ the machinery of closure operators, on the $\\pi_1$-subgroup lattice, defined in terms of test maps from one-dimensional domains.", "revisions": [ { "version": "v1", "updated": "2019-09-15T23:22:29.000Z" } ], "analyses": { "subjects": [ "57M05", "08A65", "55Q52", "20L05", "55Q05" ], "keywords": [ "fundamental groupoid", "scattered products", "countably infinite linear orders", "first countable space", "closure operators" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }