Gorenstein homological invariants and monoidal model categories of Hopf algebras

Wei Ren; Ruipeng Zhu

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arXiv · 2601.20249

Gorenstein homological invariants and monoidal model categories of Hopf algebras

Wei Ren·Ruipeng Zhu

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Abstract

Let $H$ be a Hopf algebra over a field $k$ with a bijective antipode. It is proved that the Gorenstein global dimension of $H$ coincides with the Gorenstein projective dimension of the trivial left (or right) $H$-module $k$. Then, $H$ is finite dimensional if and only if the Gorenstein projective dimension of $k$ is trivial. Although monoidal Morita-Takeuchi equivalence of Hopf algebras does not preserve the global dimension, we demonstrate that it does preserve the Gorenstein global dimension and the Artin-Schelter Gorenstein property; this supports Brown-Goodearl's question of whether every noetherian (affine) Hopf algebra is AS Gorenstein. Finally, for $H$ and an $H$-Galois object $B$, we show the categories of modules $_H\mathcal{M}$ and $_B\mathcal{M}_B^H$ are monoidal model categories regarding Gorenstein projective model structure, provided that the Gorenstein global dimension of $H$ is finite. The corresponding stable categories are tensor triangulated categories.

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Wei Ren, Ruipeng Zhu. 2026-01-28. Gorenstein homological invariants and monoidal model categories of Hopf algebras. https://arxiv.org/abs/2601.20249

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