Teoria degli operatori intermedi e applicazioni: risultati generali

Lanzara, Flavia

Lanzara, Flavia

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni, Tome 3 (1992), p. 79-101 / Harvested from Biblioteca Digitale Italiana di Matematica

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Résumé
Abstract

Mediante l'uso della teoria dei problemi intermedi vengono dati metodi di calcolo per gli operatori di Green e per le relative funzioni di Green di problemi del tipo: data $f \in S$ , determinare $u \in H$ tale che ${(T u, v)}_{H} = {(f, v)}_{S}$ , $\forall v \in H$ , dove $S$ ed $H$ sono spazi di Hilbert, $H \subset S$ , $T$ è un operatore lineare da $H$ in $H$ che verifica opportune ipotesi. Si ottengono maggiorazioni esplicite «a priori», tanto prossime a quella ottimale quanto si vuole.

Problems of the following kind are considered: ${(T u, v)}_{H} = {(f, v)}_{S}$ , $f \in S$ , $u \in H$ , $\forall v \in H$ , vector $f$ is given, vector $u$ is the «unknown». $H$ is a subspace of the Hilbert space $S$ . $T$ is a linear operator from $H$ to $H$ which satisfies suitable hypotheses. By using the theory of intermediate operators methods for the calculus of the «Green operators» and of the relevant «Green functions» are given. Explicit «a priori» estimates are obtained which are as close as we wish to the optimal ones.

Publié le : 1992-06-01

MR 1170206 | Zbl 0777.47012

@article{RLIN_1992_9_3_2_79_0,
     author = {Flavia Lanzara},
     title = {Teoria degli operatori intermedi e applicazioni: risultati generali},
     journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni},
     volume = {3},
     year = {1992},
     pages = {79-101},
     zbl = {0777.47012},
     mrnumber = {1170206},
     language = {it},
     url = {http://dml.mathdoc.fr/item/RLIN_1992_9_3_2_79_0}
}

Lanzara, Flavia. Teoria degli operatori intermedi e applicazioni: risultati generali. Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni, Tome 3 (1992) pp. 79-101. http://gdmltest.u-ga.fr/item/RLIN_1992_9_3_2_79_0/

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