{"title":"Euclidean designs obtained from spherical embedding of coherent configurations","authors":"Aiguo Wang, Yan Zhu","doi":"10.1002/jcd.21871","DOIUrl":null,"url":null,"abstract":"<p>Coherent configurations are a generalization of association schemes. Motivated by the recent study of <i>Q</i>-polynomial coherent configurations, in this paper, we study the spherical embedding of a <i>Q</i>-polynomial coherent configuration into some eigenspace by a primitive idempotent. We present a necessary and sufficient condition when the embedding becomes a Euclidean <math>\n <semantics>\n <mrow>\n <mi>t</mi>\n </mrow>\n <annotation> $t$</annotation>\n </semantics></math>-design (on two concentric spheres) in terms of the Krein numbers for <math>\n <semantics>\n <mrow>\n <mi>t</mi>\n \n <mo>≤</mo>\n \n <mn>4</mn>\n </mrow>\n <annotation> $t\\le 4$</annotation>\n </semantics></math>. In addition, we obtain some Euclidean 2- or 3-designs from spherical embedding of coherent configurations including tight relative 4- or 5-designs in binary Hamming schemes and the union of derived designs of a tight 4-design in Hamming schemes.</p>","PeriodicalId":15389,"journal":{"name":"Journal of Combinatorial Designs","volume":"31 3","pages":"143-161"},"PeriodicalIF":0.5000,"publicationDate":"2022-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Combinatorial Designs","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/jcd.21871","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
Coherent configurations are a generalization of association schemes. Motivated by the recent study of Q-polynomial coherent configurations, in this paper, we study the spherical embedding of a Q-polynomial coherent configuration into some eigenspace by a primitive idempotent. We present a necessary and sufficient condition when the embedding becomes a Euclidean -design (on two concentric spheres) in terms of the Krein numbers for . In addition, we obtain some Euclidean 2- or 3-designs from spherical embedding of coherent configurations including tight relative 4- or 5-designs in binary Hamming schemes and the union of derived designs of a tight 4-design in Hamming schemes.
期刊介绍:
The Journal of Combinatorial Designs is an international journal devoted to the timely publication of the most influential papers in the area of combinatorial design theory. All topics in design theory, and in which design theory has important applications, are covered, including:
block designs, t-designs, pairwise balanced designs and group divisible designs
Latin squares, quasigroups, and related algebras
computational methods in design theory
construction methods
applications in computer science, experimental design theory, and coding theory
graph decompositions, factorizations, and design-theoretic techniques in graph theory and extremal combinatorics
finite geometry and its relation with design theory.
algebraic aspects of design theory.
Researchers and scientists can depend on the Journal of Combinatorial Designs for the most recent developments in this rapidly growing field, and to provide a forum for both theoretical research and applications. All papers appearing in the Journal of Combinatorial Designs are carefully peer refereed.