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Duality and Rational Modules in Hopf Algebras over Commutative Rings

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 نشر من قبل F. J. Lobillo
 تاريخ النشر 2000
  مجال البحث
والبحث باللغة English
 تأليف J. Y. Abuhlail




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Let $A$ be an algebra over a commutative ring $R$. If $R$ is noetherian and $A^circ$ is pure in $R^A$, then the categories of rational left $A$-modules and right $A^circ$-comodules are isomorphic. In the Hopf algebra case, we can also strengthen the Blattner-Montgomery duality theorem. Finally, we give sufficient conditions to get the purity of $A^circ$ in $R^A$.



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