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20242026
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6 papers · 1 filter

math.CO2026

Quantizing Delsarte Theory

Ryutaro Misawa

We develop Delsarte theory for quantum association schemes, allowing both composition and the quantum Schur product to be noncommutative. A MacWilliams identity and positivity of t…

math.CO2026

Spherical Designs with Infinite Harmonic Strength

Ryutaro Misawa, Yusaku Nishimura

In this paper, we study the existence problem for spherical \(T\)-designs on the \(d\)-dimensional sphere, where \(T\) is an infinite subset of \(\mathbb N\). We show that, if \(d\…

math.CO2026

Explicit construction of spherical - and -designs

Ryutaro Misawa

This paper develops an explicit and implementable framework for constructing spherical designs by lifting point sets from tight fusion frames. By combining existing ingredients, we…

math.CO2026

Constructing spherical designs using tight -fusion frames

Ryutaro Misawa

In this paper, we study conditions under which a finite subset of the unit sphere becomes a spherical -design, when is constructed by the…

math.CO2025

Spherical Designs on of Finite Harmonic Strength

Ryutaro Misawa, Yusaku Nishimura

We study exact harmonic strengths of finite spherical designs on the unit circle. For a nonempty finite set \(X\subset S^1\), let \(\Hst(X)\) be the set of positive integers \(k\)…

math.CO2024

Antipodality of spherical designs with odd harmonic indices

Ryutaro Misawa, Akihiro Munemasa, Masanori Sawa

We determine the smallest size of a non-antipodal spherical design with harmonic indices to be , where is a positive integer. This is achieved by pro…