{ "id": "1412.4268", "version": "v1", "published": "2014-12-13T19:04:22.000Z", "updated": "2014-12-13T19:04:22.000Z", "title": "The strong Pytkeev property in topological spaces", "authors": [ "Taras Banakh", "Arkady Leiderman" ], "comment": "15 pages. arXiv admin note: text overlap with arXiv:1311.1468", "categories": [ "math.GN" ], "abstract": "A topological space $X$ has the strong Pytkeev property at a point $x\\in X$ if there exists a countable family $\\mathcal N$ of subsets of $X$ such that for each neighborhood $O_x\\subset X$ and subset $A\\subset X$ accumulating at $x$, there is a set $N\\in\\mathcal N$ such that $N\\subset O_x$ and $N\\cap A$ is infinite. We prove that for any $\\aleph_0$-space $X$ and any space $Y$ with the strong Pytkeev property at a point $y\\in Y$ the function space $C_k(X,Y)$ has the strong Pytkeev property at the constant function $X\\to \\{y\\}\\subset Y$. If the space $Y$ is rectifiable, then the function space $C_k(X,Y)$ is rectifiable and has the strong Pytkeev property at each point. We also prove that for any pointed spaces $(X_n,*_n)$, $n\\in\\omega$, with the strong Pytkeev property their Tychonoff product and their small box-product both have the strong Pytkeev property at the distinguished point. We prove that a sequential rectifiable space $X$ has the strong Pytkeev property if and only if $X$ is metrizable or contains a clopen submetrizable $k_\\omega$-subspace. A locally precompact topological group is metrizable if and only if it contains a dense subgroup with the strong Pytkeev property.", "revisions": [ { "version": "v1", "updated": "2014-12-13T19:04:22.000Z" } ], "analyses": { "subjects": [ "54E20", "54C35", "22A30" ], "keywords": [ "strong pytkeev property", "topological space", "function space", "locally precompact topological group", "tychonoff product" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1412.4268B" } } }