An affine PI Hopf algebra not finite over a normal commutative Hopf subalgebra

Shlomo Gelaki; Edward S. Letzter

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arXiv · math/0112038

An affine PI Hopf algebra not finite over a normal commutative Hopf subalgebra

Shlomo Gelaki·Edward S. Letzter

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Abstract

In formulating a generalized framework to study certain noncommutative algebras naturally arising in representation theory, K. A. Brown asked if every finitely generated Hopf algebra satisfying a polynomial identity was finite over a normal commutative Hopf subalgebra. In this note we show that Radford's biproduct, applied to the enveloping algebra of the Lie superalgebra pl(1,1), provides a noetherian prime counterexample.

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Shlomo Gelaki, Edward S. Letzter. 2001-12-04. An affine PI Hopf algebra not finite over a normal commutative Hopf subalgebra. https://arxiv.org/abs/math/0112038

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