A condition of admissibility for generalized Alexander quandles

Katsunori Arai; Keisuke Himeno; Ryoya Kai; Yuko Ozawa

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arXiv · 2608.25345

A condition of admissibility for generalized Alexander quandles

Katsunori Arai·Keisuke Himeno·Ryoya Kai·Yuko Ozawa

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Abstract

A typical example of a quandle is the conjugation quandle. A quandle is said to be admissible if it is isomorphic to a conjugation quandle. We study the admissibility problem for quandles, that is, determining whether a given quandle is admissible. In particular, we focus on generalized Alexander quandles, which are groups equipped with quandle structures defined by group automorphisms. In this paper, we provide a sufficient condition for admissibility in terms of geometric properties of quandles: namely, if every antipodal set in each algebraically connected component consists of a single point, then the quandle is admissible. This result generalizes previous results on generalized Alexander quandles.

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Katsunori Arai, Keisuke Himeno, Ryoya Kai, Yuko Ozawa. 2026-08-26. A condition of admissibility for generalized Alexander quandles. https://arxiv.org/abs/2608.25345

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