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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">najo</journal-id><journal-title-group><journal-title xml:lang="en">Nanosystems: Physics, Chemistry, Mathematics</journal-title><trans-title-group xml:lang="ru"><trans-title>Наносистемы: физика, химия, математика</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2220-8054</issn><issn pub-type="epub">2305-7971</issn><publisher><publisher-name>Университет ИТМО</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17586/2220-8054-2016-7-2-290-302</article-id><article-id custom-type="elpub" pub-id-type="custom">najo-827</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>INVITED SPEAKERS</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>INVITED SPEAKERS</subject></subj-group></article-categories><title-group><article-title>Boundary triples for Schrӧdinger operators with singular interactions on hypersurfaces</article-title><trans-title-group xml:lang="ru"><trans-title>Boundary triples for Schrӧdinger operators with singular interactions on hypersurfaces</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Behrndt</surname><given-names>J.</given-names></name><name name-style="western" xml:lang="en"><surname>Behrndt</surname><given-names>J.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Steyrergasse 30, 8010 Graz</p></bio><bio xml:lang="en"><p>Steyrergasse 30, 8010 Graz</p></bio><email xlink:type="simple">behrndt@tugraz.at</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Langer</surname><given-names>M.</given-names></name><name name-style="western" xml:lang="en"><surname>Langer</surname><given-names>M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>26 Richmond Street, Glasgow G1 1XH</p></bio><bio xml:lang="en"><p>26 Richmond Street, Glasgow G1 1XH</p></bio><email xlink:type="simple">m.langer@strath.ac.uk</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Lotoreichik</surname><given-names>V.</given-names></name><name name-style="western" xml:lang="en"><surname>Lotoreichik</surname><given-names>V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>250 68 ˇRez near Prague</p></bio><bio xml:lang="en"><p>250 68 ˇRez near Prague</p></bio><email xlink:type="simple">lotoreichik@ujf.cas.cz</email><xref ref-type="aff" rid="aff-3"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Institut fur Numerische Mathematik, Technische Universitat Graz</institution></aff><aff xml:lang="en"><institution>Institut fur Numerische Mathematik, Technische Universitat Graz</institution></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Department of Mathematics and Statistics, University of Strathclyde</institution></aff><aff xml:lang="en"><institution>Department of Mathematics and Statistics, University of Strathclyde</institution></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Department of Theoretical Physics, Nuclear Physics Institute CAS</institution></aff><aff xml:lang="en"><institution>Department of Theoretical Physics, Nuclear Physics Institute CAS</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2016</year></pub-date><pub-date pub-type="epub"><day>13</day><month>08</month><year>2025</year></pub-date><volume>7</volume><issue>2</issue><issue-title>Special Issue</issue-title><fpage>290</fpage><lpage>302</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Behrndt J., Langer M., Lotoreichik V., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Behrndt J., Langer M., Lotoreichik V.</copyright-holder><copyright-holder xml:lang="en">Behrndt J., Langer M., Lotoreichik V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://nanojournal.ifmo.ru/jour/article/view/827">https://nanojournal.ifmo.ru/jour/article/view/827</self-uri><abstract><p>The self-adjoint Schr¨odinger operator Aδ,α with a δ-interaction of constant strength α supported on a compact smooth hypersurface C is viewed as a self-adjoint extension of a natural underlying symmetric operator S in L2(Rn). The aim of this note is to construct a boundary triple for S∗ and a self-adjoint parameter Θδ,α in the boundary space L2(C) such that Aδ,α corresponds to the boundary condition induced by Θδ,α. As a consequence, the well-developed theory of boundary triples and their Weyl functions can be applied. This leads, in particular, to a Krein-type resolvent formula and a description of the spectrum of Aδ,α in terms of the Weyl function and Θδ,α.</p></abstract><trans-abstract xml:lang="ru"><p>The self-adjoint Schr¨odinger operator Aδ,α with a δ-interaction of constant strength α supported on a compact smooth hypersurface C is viewed as a self-adjoint extension of a natural underlying symmetric operator S in L2(Rn). The aim of this note is to construct a boundary triple for S∗ and a self-adjoint parameter Θδ,α in the boundary space L2(C) such that Aδ,α corresponds to the boundary condition induced by Θδ,α. As a consequence, the well-developed theory of boundary triples and their Weyl functions can be applied. This leads, in particular, to a Krein-type resolvent formula and a description of the spectrum of Aδ,α in terms of the Weyl function and Θδ,α.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>Boundary triple</kwd><kwd>Weyl function</kwd><kwd>Schrӧdinger operator</kwd><kwd>singular potential</kwd><kwd>δ-interaction</kwd><kwd>hypersurface</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Boundary triple</kwd><kwd>Weyl function</kwd><kwd>Schrӧdinger operator</kwd><kwd>singular potential</kwd><kwd>δ-interaction</kwd><kwd>hypersurface</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">J. Behrndt and V. Lotoreichik gratefully acknowledge financial support by the Austrian Science Fund (FWF): Project P 25162-N26. J. Behrndt also wishes to thank Professor Igor Popov for the pleasant and fruitful research stay at the ITMO University in St. Petersburg in September 2015. V. Lotoreichik was also supported by the Czech Science Foundation (GA CR) under the project 14-06818S.</funding-statement><funding-statement xml:lang="en">J. Behrndt and V. Lotoreichik gratefully acknowledge financial support by the Austrian Science Fund (FWF): Project P 25162-N26. J. Behrndt also wishes to thank Professor Igor Popov for the pleasant and fruitful research stay at the ITMO University in St. Petersburg in September 2015. V. Lotoreichik was also supported by the Czech Science Foundation (GA CR) under the project 14-06818S.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Br¨uning J., Geyler V., Pankrashkin K. Spectra of self-adjoint extensions and applications to solvable Schr¨odinger operators. Rev. Math. Phys., 2008, 20, P. 1–70.</mixed-citation><mixed-citation xml:lang="en">Br¨uning J., Geyler V., Pankrashkin K. 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