activity
20122026
most citedUpper bounds for -distance sets and equiangular lines

16 citations · 53 across the 30 of their papers we have counts for

collaborators

32 papers

math.CO2026

Nonexistence of Strongly Regular Graphs via Gegenbauer Positivity and SRG Counting

Zhen-Qi Liao, Jiaxin Wang, Wei-Hsuan Yu +1

This paper develops a natural extension of the multipoint spherical semidefinite method of Liao and Yu~\cite{LY}, studying the interaction between semidefinite programming and stro…

math.AG2026

On the structure and generic non-Cartesianity of polynomials in product spaces

Chun-Yen Shen, Tuyen Trung Truong, Wei-Hsuan Yu

We develop a general theory of Cartesian and non-Cartesian polynomials on products of complex spaces . We prove that, for an…

math.CO2025

Constructions of Large m-Distance Sets on Triangular Lattice

Li-Ren Bao, Wei-Hsuan Yu

An -distance set is a collection of points such that the distances between any two points have possible values. We use two different methods to construct large -distance…

math.CO2025

Bounds on two-distance sets in Euclidean space and Unit Sphere

Wei-Chun Chen, Wei-Hsuan Yu

We establish upper bounds for the size of two-distance sets in Euclidean space and spherical two-distance sets. The main recipe for obtaining upper bounds is the spectral method. W…

math.CO2025

Hegedus' Conjecture and Tighter Upper Bounds for Equidistant Codes in Hamming Spaces

Sihuang Hu, Hexiang Huang, Wei-Hsuan Yu

An equidistant code is a code in the Hamming space such that two distinct codewords have the same Hamming distance. This paper investigates the bounds for equidistant codes in Hamm…

math.CO2024

Sharing tea on a graph

J. Pascal Gollin, Kevin Hendrey, Hao Huang +6

Motivated by the analysis of consensus formation in the Deffuant model for social interaction, we consider the following procedure on a graph . Initially, there is one unit of t…

math.RT2023★ 1 cited

On character table of Clifford groups

Chin-Yen Lee, Wei-Hsuan Yu, Yung-Ning Peng +1

Based on a presentation of and the help of [GAP], we construct the character table of the Clifford group for . As an application, we can ef…

math.CO2023★ 1 cited

Stability for hyperplane covers

Shagnik Das, Valjakas Djaljapayan, Yen-chi Roger Lin +1

An almost -cover of the hypercube is a collection of hyperplanes that avoids the origin and covers every other vertex at least times. When is large wit…

math.CO2022★ 1 cited

On the two-distance embedding in real Euclidean space of coherent configuration of type (2,2;3)

Eiichi Bannai, Etsuko Bannai, Chin-Yen Lee +2

Finding the maximum cardinality of a -distance set in Euclidean space is a classical problem in geometry. Lisoněk in 1997 constructed a maximum -distance set in …

math.CO2022★ 2 cited

On the size of maximal binary codes with 2, 3, and 4 distances

Alexander Barg, Alexey Glazyrin, Wei-Jiun Kao +3

We address the maximum size of binary codes and binary constant weight codes with few distances. Previous works established a number of bounds for these quantities as well as the e…

quant-ph2022

Quantum state tomography via non-convex Riemannian gradient descent

Ming-Chien Hsu, En-Jui Kuo, Wei-Hsuan Yu +2

The recovery of an unknown density matrix of large size requires huge computational resources. The recent Factored Gradient Descent (FGD) algorithm and its variants achieved state-…

math.CO2022

Semidefinite programming bounds for few-distance sets in the Hamming and Johnson spaces

Alexander Barg, Ching-Yi Lai, Pin-Chieh Tseng +1

We study the maximum cardinality problem of a set of few distances in the Hamming and Johnson spaces. We formulate semidefinite programs for this problem and extend the 2011 works…

math.CO2022

Semidefinite programming bounds for complex spherical codes

Wei-Jiun Kao, Sho Suda, Wei-Hsuan Yu

A complex spherical code is a finite subset on the unit sphere in . A fundamental problem on complex spherical codes is to find upper bounds for those with prescribed…

math.CO2022

Four-point semidefinite bound for equiangular lines

Wei-Jiun Kao, Wei-Hsuan Yu

A set of lines in passing through the origin is called equiangular if any two lines in the set form the same angle. We proved an alternative version of the three-poi…

cs.IT2022★ 3 cited

Semidefinite programming bounds for binary codes from a split Terwilliger algebra

Pin-Chieh Tseng, Ching-Yi Lai, Wei-Hsuan Yu

We study the upper bounds for , the maximum size of codewords with length and Hamming distance at least . Schrijver studied the Terwilliger algebra of the Hamming sc…

math.CO2022

The real equiangular tight frames obtained from rank graphs

Eiichi Bannai, Etsuko Bannai, Chin-Yen Lee +2

We present all nontrivial real equiangular tight frames in obtained as spherical embeddings of primitive rank graphs on vertices, and those…

math.CO2021

Improvement of generalization of Larman-Rogers-Seidel's theorem

Cheng-Jui Yeh, Wei-Hsuan Yu

A finite set in the -dimensional Euclidean space is called an -distance set if the set of distances between any two distinct points of has size . In 1977, Larman-R…

math.CO2020

Bounds on antipodal spherical designs with few angles

Zhiqiang Xu, Zili Xu, Wei-Hsuan Yu

A finite subset on the unit sphere is called an -distance set with strength if its angle set $A(X):=\{\langle \mathbf{x},\mathbf{y}\rangle : \mathbf{x…

math.CO2020★ 1 cited

Semidefinite Programming Bounds For Spherical Three-distance Sets

Feng-Yuan Liu, Wei-Hsuan Yu

A spherical three-distance set is a finite collection of unit vectors in such that for each pair of distinct vectors has three inner product values. We use the…

math.CO2020★ 2 cited

The Lemmens-Seidel conjecture and forbidden subgraphs

Meng-Yue Cao, Jack H, Koolen +2

In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle is true. Our main tool is forbidden subgr…

stat.ME2019

Numerical computation of triangular complex spherical designs with small mesh ratio

Yu Guang Wang, Robert S. Womersley, Hau-Tieng Wu +1

This paper provides triangular spherical designs for the complex unit sphere by exploiting the natural correspondence between the complex unit sphere in dimensions and th…

math.CO2018★ 1 cited

Equiangular lines and the Lemmens-Seidel conjecture

Yen-chi Roger Lin, Wei-Hsuan Yu

In this paper, claims by Lemmens and Seidel in 1973 about equiangular sets of lines with angle are proved by carefully analyzing pillar decompositions, with the aid of the un…

math.CO2018

New code upper bounds for the folded n-cube

Lihang Hou, Bo Hou, Suogang Gao +1

Let denote a distance-regular graph. The maximum size of codewords with minimum distance at least is denoted by . Let denote the folded -cube $H(n,2)…

math.CO2018★ 2 cited

Saturated configuration and new large construction of equiangular lines

Yen-chi Roger Lin, Wei-Hsuan Yu

A set of lines through the origin in Euclidean space is called equiangular when any pair of lines from the set intersects with each other at a common angle. We study the maximum si…