3 papers
math.RA2025
On Takeuchi's correspondence
Serge Skryabin
In this paper we review the Takeuchi correspondence between right coideal subalgebras and left -module factor coalgebras of a Hopf algebra with bijective antipode. We are especi…
math.RA2020
Flatness over PI coideal subalgebras
Serge Skryabin
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 sa…
math.RA2020
Flatness of Noetherian Hopf algebras over coideal subalgebras
Serge Skryabin
It is proved in the paper that a Noetherian residually finite dimensional Hopf algebra is a flat module over any right Noetherian right coideal subalgebra. In the case of Hopf suba…