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arXiv · 2006.07878

Flatness over PI coideal subalgebras

Serge Skryabin
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Abstract

Under the assumption that a residually finite dimensional Hopf algebra H has an Artinian ring of fractions it is proved that H is a flat module over any right coideal subalgebra satisfying a polynomial identity and is faithfully flat over any polynomial identity Hopf subalgebra. As a consequence we find a large class of Hopf algebras which are flat over all coideal subalgebras and are faithfully flat over all Hopf subalgebras.

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Serge Skryabin. 2020-06-14. Flatness over PI coideal subalgebras. https://arxiv.org/abs/2006.07878

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