Spectral analysis for a discontinuous second order elliptic operator

<p>The spectrum of a second order elliptic operator <em>S</em>, with ellipticity constant <em>α</em> discontinuous in a point, is studied in <em>L^p</em> spaces. It turns out that, for <em>(α, p)</em> in a set <em>A</em>, classical re...

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Bibliographic Details
Main Authors: Paolo Manselli, Francesco Ragnedda
Format: Article
Language:English
Published: Università degli Studi di Catania 2003-05-01
Series:Le Matematiche
Online Access:http://www.dmi.unict.it/ojs/index.php/lematematiche/article/view/181
Description
Summary:<p>The spectrum of a second order elliptic operator <em>S</em>, with ellipticity constant <em>α</em> discontinuous in a point, is studied in <em>L^p</em> spaces. It turns out that, for <em>(α, p)</em> in a set <em>A</em>, classical results for the spectrum of smooth elliptic operators (see e.g. [3]) remain true for <em>S</em>; in particular, it is proved that <em>S</em> is the infinitesimal generator of an holomorphic semigroup . If <em>(α, p)</em> not in<em> A</em>, then the spectrum of <em>S</em> is the whole complex plane.</p>
ISSN:0373-3505
2037-5298