Critical visibility and outward rays
The notion of clear visibility has appeared recently in the literature concerning the geometry of starshaped sets. A somewhat converse notion, that of critical visibility, is explored here. As a by-product it is proved that the points of local nonconvexity of a closed connected set S determine the n...
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todo:paper_00472468_v33_n1-2_p155_Toranzos2023-10-03T14:52:19Z Critical visibility and outward rays Toranzos, F.A. The notion of clear visibility has appeared recently in the literature concerning the geometry of starshaped sets. A somewhat converse notion, that of critical visibility, is explored here. As a by-product it is proved that the points of local nonconvexity of a closed connected set S determine the nontrivial portions of the boundary of the star of a point in S. Paragraph 4 is devoted to the study of the concepts of outward ray through a boundary point and inner stem of that point. A new characterization of the convex kernel of a starshaped set results from this study, and Krasnoselsky-type theorems are obtained in the planar case. © 1988 Birkhäuser Verlag. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00472468_v33_n1-2_p155_Toranzos |
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Universidad de Buenos Aires |
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I-28 |
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R-134 |
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
description |
The notion of clear visibility has appeared recently in the literature concerning the geometry of starshaped sets. A somewhat converse notion, that of critical visibility, is explored here. As a by-product it is proved that the points of local nonconvexity of a closed connected set S determine the nontrivial portions of the boundary of the star of a point in S. Paragraph 4 is devoted to the study of the concepts of outward ray through a boundary point and inner stem of that point. A new characterization of the convex kernel of a starshaped set results from this study, and Krasnoselsky-type theorems are obtained in the planar case. © 1988 Birkhäuser Verlag. |
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JOUR |
author |
Toranzos, F.A. |
spellingShingle |
Toranzos, F.A. Critical visibility and outward rays |
author_facet |
Toranzos, F.A. |
author_sort |
Toranzos, F.A. |
title |
Critical visibility and outward rays |
title_short |
Critical visibility and outward rays |
title_full |
Critical visibility and outward rays |
title_fullStr |
Critical visibility and outward rays |
title_full_unstemmed |
Critical visibility and outward rays |
title_sort |
critical visibility and outward rays |
url |
http://hdl.handle.net/20.500.12110/paper_00472468_v33_n1-2_p155_Toranzos |
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AT toranzosfa criticalvisibilityandoutwardrays |
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1807323350454763520 |