Homothetic covering and the illumination problem of convex bodies
At a first glance, the problem of illuminating the boundary of a convex body by light sources and the problem of covering a convex body by smaller homothetic copies seem different. But actually they both are incarnations of the same open problem in convex and discrete geometry, the illumination conj...
- Autores:
-
Rodríguez Sierra, Santiago
- Tipo de recurso:
- Trabajo de grado de pregrado
- Fecha de publicación:
- 2024
- Institución:
- Universidad de los Andes
- Repositorio:
- Séneca: repositorio Uniandes
- Idioma:
- eng
- OAI Identifier:
- oai:repositorio.uniandes.edu.co:1992/75513
- Acceso en línea:
- https://hdl.handle.net/1992/75513
- Palabra clave:
- Convex body
Illumination by points or directions
Homothetic covering
Polytope
Gohberg-Markus-Hadwiger problem
Regular boundary
Erdös-Rogers upper bound
Matemáticas
- Rights
- openAccess
- License
- Attribution-NonCommercial-NoDerivatives 4.0 International
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dc.title.eng.fl_str_mv |
Homothetic covering and the illumination problem of convex bodies |
title |
Homothetic covering and the illumination problem of convex bodies |
spellingShingle |
Homothetic covering and the illumination problem of convex bodies Convex body Illumination by points or directions Homothetic covering Polytope Gohberg-Markus-Hadwiger problem Regular boundary Erdös-Rogers upper bound Matemáticas |
title_short |
Homothetic covering and the illumination problem of convex bodies |
title_full |
Homothetic covering and the illumination problem of convex bodies |
title_fullStr |
Homothetic covering and the illumination problem of convex bodies |
title_full_unstemmed |
Homothetic covering and the illumination problem of convex bodies |
title_sort |
Homothetic covering and the illumination problem of convex bodies |
dc.creator.fl_str_mv |
Rodríguez Sierra, Santiago |
dc.contributor.advisor.none.fl_str_mv |
Dann, Susanna |
dc.contributor.author.none.fl_str_mv |
Rodríguez Sierra, Santiago |
dc.contributor.jury.none.fl_str_mv |
Bogart, Tristram |
dc.subject.keyword.eng.fl_str_mv |
Convex body Illumination by points or directions Homothetic covering Polytope Gohberg-Markus-Hadwiger problem Regular boundary Erdös-Rogers upper bound |
topic |
Convex body Illumination by points or directions Homothetic covering Polytope Gohberg-Markus-Hadwiger problem Regular boundary Erdös-Rogers upper bound Matemáticas |
dc.subject.themes.spa.fl_str_mv |
Matemáticas |
description |
At a first glance, the problem of illuminating the boundary of a convex body by light sources and the problem of covering a convex body by smaller homothetic copies seem different. But actually they both are incarnations of the same open problem in convex and discrete geometry, the illumination conjecture. This conjecture is also known as the Gohberg-Markus-Hadwiger conjecture, referring to some of its original proposers. In fact the two different versions of the problem were poses independently of one another and later shown that they were equivalent.\\ In 1957 Hadwiger posed the problem of finding the smallest natural number $N$ such that any $d$-dimensional convex body can be covered by the interior of a union of at the most $N$ of its translates. In the 1960 the problem was translated in terms of smaller homothetical copies of the original body. Later, in 1960, Boltyanski introduced the problem of illuminating the boundary of a convex body by the smallest amount of external light sources. For a given convex body we call the answer to both of the previous problems the illumination number of the body. It is conjectured that every $d$-dimensional convex body has an illumination number smaller than or equal to $2^d$ with equality for $d$-dimensional parallelepipeds. It turns, out that this is one of the central problems in convex and discrete geometry.\\ Our work consists of studying the advancements done to solve the conjecture in various possible approaches. |
publishDate |
2024 |
dc.date.issued.none.fl_str_mv |
2024-12-03 |
dc.date.accessioned.none.fl_str_mv |
2025-01-21T12:47:23Z |
dc.date.available.none.fl_str_mv |
2025-01-21T12:47:23Z |
dc.type.none.fl_str_mv |
Trabajo de grado - Pregrado |
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info:eu-repo/semantics/bachelorThesis |
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info:eu-repo/semantics/acceptedVersion |
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http://purl.org/coar/resource_type/c_7a1f |
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http://purl.org/coar/resource_type/c_7a1f |
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acceptedVersion |
dc.identifier.uri.none.fl_str_mv |
https://hdl.handle.net/1992/75513 |
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instname:Universidad de los Andes |
dc.identifier.reponame.none.fl_str_mv |
reponame:Repositorio Institucional Séneca |
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repourl:https://repositorio.uniandes.edu.co/ |
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dc.language.iso.none.fl_str_mv |
eng |
language |
eng |
dc.relation.references.none.fl_str_mv |
Hugo Hadwiger. Ungelöste probleme nr. 20. Elemente der Mathematik, 12:121, 1957. I. Ts. Gohberg and A. S. Markus. Certain problem about the covering of convex sets with homothetic ones. Izvestiya Moldavskogo Filiala Akademii Nauk SSSR, 10:87–90, 1960. V. Boltyanski. The problem of illuminating the boundary of a convex body. Izv. Mold. Fil. AN SSSR, 76:77–84, 1960. Benulf Weißbach. Invariant illumination of convex bodies. (invariante beleuchtung konvexer köper.). Beiträge zur Algebra und Geometrie, 37(1):9–15, 1996. Paul Erd¨os and C. Ambrose Rogers. The star number of coverings of space with convex bodies. Acta Arithmetica, 9:41–45, 1964. Karoly Bezdek and Muhammad A. Khan. The geometry of homothetic covering and illumination, 2016. S.P. Boyd and L. Vandenberghe. Convex Optimization. Berichte über verteilte messysteme. Cambridge University Press, 2004. V. Boltyanski, H. Martini, and P.S. Soltan. Excursions into Combinatorial Geometry. Universitext. Springer Berlin Heidelberg, 1996. C. A. Rogers and G. C. Shephard. The difference body of a convex body. Archiv der Mathematik, 8:220–233, 8 1957. Paul Erdös and C. Ambrose Rogers. Covering space with convex bodies. Acta Arithmetica, 7(3):281–285, 1962. Edmund Hlawka. Zur geometrie der zahlen. Mathematische Zeitschrift, 49:285–312, 1943. |
dc.rights.en.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International |
dc.rights.uri.none.fl_str_mv |
http://creativecommons.org/licenses/by-nc-nd/4.0/ |
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dc.format.extent.none.fl_str_mv |
72 páginas |
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Universidad de los Andes |
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Matemáticas |
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Facultad de Ciencias |
dc.publisher.department.none.fl_str_mv |
Departamento de Matemáticas |
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Universidad de los Andes |
institution |
Universidad de los Andes |
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Dann, Susannavirtual::22285-1Rodríguez Sierra, SantiagoBogart, Tristram2025-01-21T12:47:23Z2025-01-21T12:47:23Z2024-12-03https://hdl.handle.net/1992/75513instname:Universidad de los Andesreponame:Repositorio Institucional Sénecarepourl:https://repositorio.uniandes.edu.co/At a first glance, the problem of illuminating the boundary of a convex body by light sources and the problem of covering a convex body by smaller homothetic copies seem different. But actually they both are incarnations of the same open problem in convex and discrete geometry, the illumination conjecture. This conjecture is also known as the Gohberg-Markus-Hadwiger conjecture, referring to some of its original proposers. In fact the two different versions of the problem were poses independently of one another and later shown that they were equivalent.\\ In 1957 Hadwiger posed the problem of finding the smallest natural number $N$ such that any $d$-dimensional convex body can be covered by the interior of a union of at the most $N$ of its translates. In the 1960 the problem was translated in terms of smaller homothetical copies of the original body. Later, in 1960, Boltyanski introduced the problem of illuminating the boundary of a convex body by the smallest amount of external light sources. For a given convex body we call the answer to both of the previous problems the illumination number of the body. It is conjectured that every $d$-dimensional convex body has an illumination number smaller than or equal to $2^d$ with equality for $d$-dimensional parallelepipeds. It turns, out that this is one of the central problems in convex and discrete geometry.\\ Our work consists of studying the advancements done to solve the conjecture in various possible approaches.Pregrado72 páginasapplication/pdfengUniversidad de los AndesMatemáticasFacultad de CienciasDepartamento de MatemáticasAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccesshttp://purl.org/coar/access_right/c_abf2Homothetic covering and the illumination problem of convex bodiesTrabajo de grado - Pregradoinfo:eu-repo/semantics/bachelorThesisinfo:eu-repo/semantics/acceptedVersionhttp://purl.org/coar/resource_type/c_7a1fTexthttp://purl.org/redcol/resource_type/TPConvex bodyIllumination by points or directionsHomothetic coveringPolytopeGohberg-Markus-Hadwiger problemRegular boundaryErdös-Rogers upper boundMatemáticasHugo Hadwiger. Ungelöste probleme nr. 20. Elemente der Mathematik, 12:121, 1957.I. Ts. Gohberg and A. S. Markus. Certain problem about the covering of convex sets with homothetic ones. Izvestiya Moldavskogo Filiala Akademii Nauk SSSR, 10:87–90, 1960.V. Boltyanski. The problem of illuminating the boundary of a convex body. Izv. Mold. Fil. AN SSSR, 76:77–84, 1960.Benulf Weißbach. Invariant illumination of convex bodies. (invariante beleuchtung konvexer köper.). Beiträge zur Algebra und Geometrie, 37(1):9–15, 1996.Paul Erd¨os and C. Ambrose Rogers. The star number of coverings of space with convex bodies. Acta Arithmetica, 9:41–45, 1964.Karoly Bezdek and Muhammad A. Khan. The geometry of homothetic covering and illumination, 2016.S.P. Boyd and L. Vandenberghe. Convex Optimization. Berichte über verteilte messysteme. Cambridge University Press, 2004.V. Boltyanski, H. Martini, and P.S. Soltan. Excursions into Combinatorial Geometry. Universitext. Springer Berlin Heidelberg, 1996.C. A. Rogers and G. C. Shephard. The difference body of a convex body. Archiv der Mathematik, 8:220–233, 8 1957.Paul Erdös and C. Ambrose Rogers. Covering space with convex bodies. Acta Arithmetica, 7(3):281–285, 1962.Edmund Hlawka. Zur geometrie der zahlen. Mathematische Zeitschrift, 49:285–312, 1943.202020476Publication1097da79-8923-4450-b773-4b6850f28517virtual::22285-11097da79-8923-4450-b773-4b6850f28517virtual::22285-1CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8805https://repositorio.uniandes.edu.co/bitstreams/e4a5880a-436b-45fc-a9b9-0ee5d973452c/download4460e5956bc1d1639be9ae6146a50347MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-82535https://repositorio.uniandes.edu.co/bitstreams/76efc7b6-fd63-49a8-acf0-7af68d5736e5/downloadae9e573a68e7f92501b6913cc846c39fMD52ORIGINALHomothetic covering and the illumination problem of convex bodies.pdfHomothetic covering and the illumination problem of convex bodies.pdfapplication/pdf1751950https://repositorio.uniandes.edu.co/bitstreams/270eecc5-243d-47ba-9a4a-ebe0931c4c21/download0978121722bfce3636866fdf20ab6b1fMD53autorizacion tesis.pdfautorizacion 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