DOI: 10.1017/s0013091526101564 ISSN: 0013-0915

Generalized Kac–Paljutkin algebras

Christian Lomp

Abstract

In this note, we construct a family of non-commutative, non-cocommutative semisimple Hopf algebras

Hn comma m $ H_{n,m} $ H n , m
of dimension
nmm exclamation mark $ n^m m! $ n m m !
over a field of characteristic zero containing a primitive
n $ n $ n
th root of unity, where
n comma m greater than or equals 2 $ n, m \geq 2 $ n , m ≥ 2
are integers. The well-known eight-dimensional Kac–Paljutkin algebra arises as the special case
upper H 2 comma 2 $ H_{2,2} $ H 2 , 2
, while the Hopf algebras previously constructed by Pansera correspond to the instances
Hn comma 2 $ H_{n,2} $ H n , 2
. Each algebra
Hn comma m $ H_{n,m} $ H n , m
is defined as an extension of the group algebra
double struck upper K upper Sigma m $ \mathbb{K} \Sigma_m $ 𝕂 Σ m
of the symmetric group by the
m $ m $ m
-fold tensor product
upper R equals double struck upper K double struck upper Z n circled times m $ R = \mathbb{K} \mathbb{Z}_n^{\otimes m} $ R = 𝕂 ℤ n ⊗ m
, where
double struck upper Z n $ \mathbb{Z}_n $ ℤ n
denotes the cyclic group of order
n $ n $ n
. This extension admits a realization as a crossed product:
Hn comma m equals double struck upper K double struck upper Z n circled times m number sign gamma upper Sigma m period $H_{n,m} = \mathbb{K} \mathbb{Z}_n^{\otimes m} \#_\gamma \Sigma_m.$ H n , m = 𝕂 ℤ n ⊗ m # γ Σ m .
In the final section, we construct a family of irreducible
m $ m $ m
-dimensional representations of
Hn comma m $ H_{n,m} $ H n , m
that are inner faithful as
upper R $ R $ R
-modules and exhibit a non-trivial inner-faithful action of a subalgebra of
Hn comma m $ H_{n,m} $ H n , m
on a quantum polynomial algebra.

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