Reduced Forms of Linear Differential Systems and the Intrinsic Galois–Lie Algebra of Katz
Symmetry, integrability and geometry: methods and applications, Tome 16 (2020) Cet article a éte moissonné depuis la source Math-Net.Ru

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Generalizing the main result of [Aparicio-Monforte A., Compoint E., Weil J.-A., J. Pure Appl. Algebra 217 (2013), 1504–1516], we prove that a linear differential system is in reduced form in the sense of Kolchin and Kovacic if and only if any differential module in an algebraic construction admits a constant basis. Then we derive an explicit version of this statement. We finally deduce some properties of the Lie algebra of Katz's intrinsic Galois group.
Keywords: linear differential systems, differential Galois theory, reduced forms.
Mots-clés : Lie algebras
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Moulay Barkatou; Thomas Cluzeau; Lucia Di Vizio; Jacques-Arthur Weil. Reduced Forms of Linear Differential Systems and the Intrinsic Galois–Lie Algebra of Katz. Symmetry, integrability and geometry: methods and applications, Tome 16 (2020). http://geodesic.mathdoc.fr/item/SIGMA_2020_16_a53/

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