{ "id": "1205.6966", "version": "v1", "published": "2012-05-31T12:20:37.000Z", "updated": "2012-05-31T12:20:37.000Z", "title": "One-point extensions of locally compact paracompact spaces", "authors": [ "M. R. Koushesh" ], "comment": "22 pages", "journal": "Bull. Iranian Math. Soc. 37 (2011), no. 4, 199-228", "categories": [ "math.GN" ], "abstract": "A space $Y$ is called an {\\em extension} of a space $X$ if $Y$ contains $X$ as a dense subspace. Two extensions of $X$ are said to be {\\em equivalent} if there is a homeomorphism between them which fixes $X$ point-wise. For two (equivalence classes of) extensions $Y$ and $Y'$ of $X$ let $Y\\leq Y'$ if there is a continuous function of $Y'$ into $Y$ which fixes $X$ point-wise. An extension $Y$ of $X$ is called a {\\em one-point extension} if $Y\\backslash X$ is a singleton. An extension $Y$ of $X$ is called {\\em first-countable} if $Y$ is first-countable at points of $Y\\backslash X$. Let ${\\mathcal P}$ be a topological property. An extension $Y$ of $X$ is called a {\\em ${\\mathcal P}$-extension} if it has ${\\mathcal P}$. In this article, for a given locally compact paracompact space $X$, we consider the two classes of one-point \\v{C}ech-complete ${\\mathcal P}$-extensions of $X$ and one-point first-countable locally-${\\mathcal P}$ extensions of $X$, and we study their order-structures, by relating them to the topology of a certain subspace of the outgrowth $\\beta X\\backslash X$. Here ${\\mathcal P}$ is subject to some requirements and include $\\sigma$-compactness and the Lindel\\\"{o}f property as special cases.", "revisions": [ { "version": "v1", "updated": "2012-05-31T12:20:37.000Z" } ], "analyses": { "subjects": [ "54D20", "54D35", "54D40", "54D45", "54E50" ], "keywords": [ "locally compact paracompact space", "one-point extension", "dense subspace", "special cases", "equivalence classes" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1205.6966K" } } }