{ "id": "2212.07077", "version": "v1", "published": "2022-12-14T07:56:13.000Z", "updated": "2022-12-14T07:56:13.000Z", "title": "The hyperspace of non-blockers of singletons, all the possible examples", "authors": [ "Alejandro Illanes", "Benjamin Vejnar" ], "categories": [ "math.GN" ], "abstract": "Given a metric continuum $X$, a nonempty proper closed subspace $B$ of $X$, does not block a point $p\\in X\\setminus B$ provided that the union of all subcontinua of $X$ containing $p$ and contained in $X\\setminus B$ is a dense subset of $X$. The collection of all nonempty proper closed subspaces $B$ of $X$ such that $B$ does not block any element of $X\\setminus B$ is denoted by $NB(F_{1}(X))$. In this paper we prove that for each completely metrizable and separable space $Z$, there exists a continuum $X$ such that $Z$ is homeomorphic to $NB(F_{1}(X))$. This answers a series of questions by Camargo, Capul\\'in, Casta\\=neda-Alvarado and Maya.", "revisions": [ { "version": "v1", "updated": "2022-12-14T07:56:13.000Z" } ], "analyses": { "subjects": [ "54B20", "54F15" ], "keywords": [ "nonempty proper closed subspace", "non-blockers", "hyperspace", "singletons", "metric continuum" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }