The Picard-Vessiot closure in differential Galois theory
Let Γ be a finite-dimensional hereditary basic algebra. We consider the radical rad Γ as a Γ-bimodule. It is known that there exists a quasi-hereditary algebra 𝓐 such that the category of matrices over rad Γ is equivalent to the category of Δ-filtered 𝓐-modules ℱ(𝓐,Δ). In this note we determine the quasi-hereditary algebra 𝓐 and prove certain properties of its module category.
We classify all complex - and -dimensional dual mock-Lie algebras by the algebraic and geometric way. Also, we find all non-trivial complex -dimensional dual mock-Lie algebras.
Les chtoucas locaux sont des analogues en égales caractéristiques des groupes -divisibles — par exemple on leur associe un module de Tate, qui est un module libre sur l’anneau d’entiers d’un corps local de caractéristique positive. Nous associons à un chtouca local une structure de Hodge (ou, plus précisément, une structure de Hodge-Pink), ce qui induit un morphisme de périodes analogue à celui construit par Rapoport et Zink. Pour les structures de Hodge-Pink définies sur une extension finie...
Using geometrical methods, Huisgen-Zimmermann showed that if M is a module with simple top, then M has no proper degeneration such that for all t. Given a module M with square-free top and a projective cover P, she showed that if and only if M has no proper degeneration where M/M ≃ N/N. We prove here these results in a more general form, for hom-order instead of degeneration-order, and we prove them algebraically. The results of Huisgen-Zimmermann follow as consequences from our results....