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arXiv · 2211.07756

Correspondence theorems for Hopf algebroids with applications to affine groupoids

Laiachi El Kaoutit·Aryan Ghobadi·Paolo Saracco·Joost Vercruysse
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Abstract

We provide a correspondence between one-sided coideal subrings and one-sided ideal two-sided coideals in an arbitrary bialgebroid. We prove that, under some expected additional conditions, this correspondence becomes bijective for Hopf algebroids. As an application, we investigate normal Hopf ideals in commutative Hopf algebroids (affine groupoid schemes) in connection with the study of normal affine subgroupoids.

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Laiachi El Kaoutit, Aryan Ghobadi, Paolo Saracco, Joost Vercruysse. 2022-11-14. Correspondence theorems for Hopf algebroids with applications to affine groupoids. https://doi.org/10.4153/s0008414x23000238

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