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arXiv · 2503.12268

Affineness on Noetherian graded rings, algebras and Hopf algebras

Huan Jia·Yinhuo Zhang
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Abstract

In this note, we show that every Noetherian graded ring with an affine degree zero part is affine. As a result, a Noetherian graded Hopf algebra whose degree zero component is a commutative or a cocommutative Hopf subalgebra is affine. Moreover, we show that the braided Hopf algebra of a Noetherian graded Hopf algebra is affine.

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Huan Jia, Yinhuo Zhang. 2025-03-15. Affineness on Noetherian graded rings, algebras and Hopf algebras. https://arxiv.org/abs/2503.12268

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