A Note on Lower Bounds for Colourful Simplicial Depth

The colourful simplicial depth problem in dimension d is to find a configuration of (d+1) sets of (d+1) points such that the origin is contained in the convex hull of each set, or colour, but contained in a minimal number of colourful simplices generated by taking one point from each set. A construc...

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Main Authors: Antoine Deza, Tamon Stephen, Feng Xie
Format: Article
Language:English
Published: MDPI AG 2013-01-01
Series:Symmetry
Subjects:
Online Access:http://www.mdpi.com/2073-8994/5/1/47
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author Antoine Deza
Tamon Stephen
Feng Xie
author_facet Antoine Deza
Tamon Stephen
Feng Xie
author_sort Antoine Deza
collection DOAJ
description The colourful simplicial depth problem in dimension d is to find a configuration of (d+1) sets of (d+1) points such that the origin is contained in the convex hull of each set, or colour, but contained in a minimal number of colourful simplices generated by taking one point from each set. A construction attaining d2 + 1 simplices is known, and is conjectured to be minimal. This has been confirmed up to d = 3, however the best known lower bound for d ≥ 4 is ⌈(d+1)2 /2 ⌉. In this note, we use a branching strategy to improve the lower bound in dimension 4 from 13 to 14.
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spelling doaj.art-3d47f16a1dc841acb829df847b5cb7fa2022-12-22T04:21:14ZengMDPI AGSymmetry2073-89942013-01-0151475310.3390/sym5010047A Note on Lower Bounds for Colourful Simplicial DepthAntoine DezaTamon StephenFeng XieThe colourful simplicial depth problem in dimension d is to find a configuration of (d+1) sets of (d+1) points such that the origin is contained in the convex hull of each set, or colour, but contained in a minimal number of colourful simplices generated by taking one point from each set. A construction attaining d2 + 1 simplices is known, and is conjectured to be minimal. This has been confirmed up to d = 3, however the best known lower bound for d ≥ 4 is ⌈(d+1)2 /2 ⌉. In this note, we use a branching strategy to improve the lower bound in dimension 4 from 13 to 14.http://www.mdpi.com/2073-8994/5/1/47colourful simplicial depthColourful Carath&#233odory Theoremdiscrete geometrypolyhedracombinatorial symmetry
spellingShingle Antoine Deza
Tamon Stephen
Feng Xie
A Note on Lower Bounds for Colourful Simplicial Depth
Symmetry
colourful simplicial depth
Colourful Carath&#233
odory Theorem
discrete geometry
polyhedra
combinatorial symmetry
title A Note on Lower Bounds for Colourful Simplicial Depth
title_full A Note on Lower Bounds for Colourful Simplicial Depth
title_fullStr A Note on Lower Bounds for Colourful Simplicial Depth
title_full_unstemmed A Note on Lower Bounds for Colourful Simplicial Depth
title_short A Note on Lower Bounds for Colourful Simplicial Depth
title_sort note on lower bounds for colourful simplicial depth
topic colourful simplicial depth
Colourful Carath&#233
odory Theorem
discrete geometry
polyhedra
combinatorial symmetry
url http://www.mdpi.com/2073-8994/5/1/47
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