Graphs and Combinatorics ( IF 0.7 ) Pub Date : 2021-03-19 , DOI: 10.1007/s00373-021-02287-9 Hirotake Kurihara
The unitary group U(n) is a symmetric space and has the point-symmetry for every point \(x\in U(n)\). A great antipodal set on U(n) is a “good” finite subset of U(n) related to the point-symmetries. On the other hand, a great antipodal set on U(n) is an analogue of a pair of antipodal points on spheres. It is known that a finite subset of a sphere is a tight spherical 1-design if and only if it is a pair of antipodal points. In this paper, we investigate a relation between great antipodal sets on U(n) and design theory on U(n). Moreover, we give a relation between a great antipodal set on U(n) and a Hamming cube graph \({\mathcal {Q}}_n\).
中文翻译:
Unit群上的对映集和设计
ary群U(n)是一个对称空间,并且对每个点\(x \ in U(n)\)具有点对称性。在一个伟大的反足一套ü(ñ)是一个“好”的穷子集ü(ñ相关点对称)。另一方面,在U(n)上设置的极大对映体类似于球体上的一对对映体点。众所周知,当且仅当它是一对对映点时,球的有限子集才是紧密球面1设计。在本文中,我们探讨大映的集之间的关系ü(ñ)和设计理论的ù(n)。此外,我们给出了U(n)上的极大对映集与汉明立方体图\({\ mathcal {Q}} _ n \)之间的关系。