Multiparameter perturbation theory of matrices and linear operators

Autor: Adam Parusinski, Guillaume Rond
Přispěvatelé: Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Mathématiques de Marseille (I2M), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), ANR-17-CE40-0023,LISA,Géométrie Lipschitz des singularités(2017), Laboratoire Jean Alexandre Dieudonné (LJAD), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Transactions of the American Mathematical Society
Transactions of the American Mathematical Society, American Mathematical Society, 2020, 373 (4), pp.2933-2948. ⟨10.1090/tran/8061⟩
Transactions of the American Mathematical Society, 2020, 373 (4), pp.2933-2948. ⟨10.1090/tran/8061⟩
ISSN: 0002-9947
1088-6850
Popis: We show that a normal matrix $A$ with coefficient in $\mathbb C[[X]]$, $X=(X_1, \ldots, X_n)$, can be diagonalized, provided the discriminant $\Delta_A $ of its characteristic polynomial is a monomial times a unit. The proof is an adaptation of the algorithm of proof of Abhyankar-Jung Theorem. As a corollary we obtain the singular value decomposition for an arbitrary matrix $A$ with coefficient in $\mathbb C[[X]]$ under a similar assumption on $\Delta_{AA^*} $ and $\Delta_{A^*A} $. We also show real versions of these results, i.e. for coefficients in $\mathbb R[[X]]$, and deduce several results on multiparameter perturbation theory for normal matrices with real analytic, quasi-analytic, or Nash coefficients.
Comment: 15 pages - to appear in Trans. Amr. Math. Soc
Databáze: OpenAIRE