<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/CINECAstyle.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-09-23T00:54:45Z</responseDate><request verb="GetRecord" identifier="oai:iris.unica.it:11584/266589" metadataPrefix="oai_dc">https://iris.unica.it/oai/request</request><GetRecord><record><header><identifier>oai:iris.unica.it:11584/266589</identifier><datestamp>2022-10-17T14:17:39Z</datestamp><setSpec>com_11584_207615</setSpec><setSpec>com_11584_111066</setSpec><setSpec>col_11584_265854</setSpec></header><metadata><oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:doc="http://www.lyncode.com/xoai" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dc="http://purl.org/dc/elements/1.1/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
<dc:title>On two problems related to the Laplace operator</dc:title>
<dc:creator>FARINA, MARIA ANTONIETTA</dc:creator>
<dc:subject>autovalore principale</dc:subject>
<dc:subject>brownian motion</dc:subject>
<dc:subject>coarea formula</dc:subject>
<dc:subject>dinamica delle popolazioni</dc:subject>
<dc:subject>dominio armonico</dc:subject>
<dc:subject>formula della coarea</dc:subject>
<dc:subject>harmonic domain</dc:subject>
<dc:subject>massimizzazione</dc:subject>
<dc:subject>maximization</dc:subject>
<dc:subject>minimization</dc:subject>
<dc:subject>minimizzazione</dc:subject>
<dc:subject>moto browniano</dc:subject>
<dc:subject>population dynamics</dc:subject>
<dc:subject>principal eigenvalue</dc:subject>
<dc:subject>rearrangements</dc:subject>
<dc:subject>riordinamenti</dc:subject>
<dc:subject>rottura della simmetria</dc:subject>
<dc:subject>symmetry breaking</dc:subject>
<dc:subject>Settore MAT/03 - Geometria</dc:subject>
<dc:description>We investigate maximization of the functional Ω → ε(Ω) where  Ω runs in the set&#xd;
of compact domains of fixed volume v in any Riemannian manifold (M; g) and&#xd;
where ε(Ω) is the mean exit time from &#xd;
 of the Brownian motion. Concerning&#xd;
this functional, we study its critical points and prove that they are harmonic&#xd;
domains. We analyze the special case of the Coarea formula when we take a&#xd;
Morse function. We investigate minimization and maximization of the principal&#xd;
eigenvalue of the Laplacian under mixed boundary conditions in case the weight&#xd;
has indefinite sign and varies in the class of rearrangements of a fixed function&#xd;
g0 defined on a smooth and bounded domain Ω&#xd;
in Rn. We prove existence&#xd;
and uniqueness results, and in special cases, we prove results of symmetry and&#xd;
results of symmetry breaking for the minimizer.</dc:description>
<dc:date>2015-04-16</dc:date>
<dc:type>info:eu-repo/semantics/doctoralThesis</dc:type>
<dc:identifier>http://hdl.handle.net/11584/266589</dc:identifier>
<dc:language>eng</dc:language>
<dc:relation>numberofpages:76</dc:relation>
<dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
<dc:publisher>Università degli Studi di Cagliari</dc:publisher>
<dc:rights>license:Non specificato</dc:rights>
</oai_dc:dc></metadata></record></GetRecord></OAI-PMH>