English

On irreducible representations of quandles

Representation Theory 2026-04-15 v1

Abstract

We consider irreducible representations of finite quandles over C\mathbb{C}. For QQ a finite quandle whose inner automorphism group Inn(Q)Inn(Q) have trivial Schur multipliers, we prove that the irreducible representations of QQ can be constructed out of what we call characters of QQ and irreducible linear represenations of the group Inn(Q)Inn(Q). For GG a finite groiup having trivial Schur multiplier or being a Schur cover of another group, we show that the irreducible representations of the conjugacy quandle Conj(G)Conj(G) can be constructed out of characters of Conj(G)Conj(G) and irreducible linear representations of the group GG. In both cases, the finite unitary irreducible representations can be determined from the results. For instance, these results allow to solve the problem of constucting irreducible represenations of the conjugacy quandles of dihedral groups and generalised quaternion groups. In general, we relate the irreducible representations of a finite quandle QQ to irreducible projective representations of Inn(Q)Inn(Q) and prove that the irreducible representations of QQ can be in theory constructed out of characters of QQ and irreducible representations of a finite quotient of the enveloping group G(Q)G(Q). The quotient is a stem extensions of Inn(Q)Inn(Q) with nucleus a finite subgroup of the center of G(Q)G(Q). This allows, using a result from the litterature, to show that the irreducible quandle representations of Conj(Sn)Conj(S_n) (SnS_n the symmetric group) can be constructed out of characters of the corresponding quandle and irreducible linear group representations of the symmetric group.

Keywords

Cite

@article{arxiv.2604.12550,
  title  = {On irreducible representations of quandles},
  author = {Mohamad Maassarani},
  journal= {arXiv preprint arXiv:2604.12550},
  year   = {2026}
}