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Kerr, Lyndsay and Lamb, Wilson and Langer, Matthias (2024) Discrete fragmentation equations with time-dependent coefficients. Discrete and Continuous Dynamical Systems - series S, 17 (5). pp. 1947-1965. ISSN 1937-1632

Langer, Matthias and Pruckner, Raphael and Woracek, Harald (2024) Canonical systems whose Weyl coefficients have dominating real part. Journal d'Analyse Mathématique, 152 (1). pp. 361-400. ISSN 0021-7670

McLauchlan, Sophie and Han, Yucen and Langer, Matthias and Majumdar, Apala (2024) The radial hedgehog solution in the Landau–de Gennes theory : effects of the bulk potentials. Physica D: Nonlinear Phenomena, 459. 134019. ISSN 0167-2789

Langer, Matthias and Woracek, Harald (2024) Karamata's theorem for regularized Cauchy transforms. Proceedings of the Royal Society of Edinburgh: Section A Mathematics. pp. 1-61. ISSN 0308-2105

Langer, Matthias and Pruckner, Raphael and Woracek, Harald (2023) Estimates for the Weyl coefficient of a two-dimensional canonical system. Annali della Scuola Normale Superiore di Pisa, Classe di Scienze. ISSN 0391-173X

Kerr, Lyndsay and Lamb, Wilson and Langer, Matthias (2020) Discrete fragmentation systems in weighted ℓ1 spaces. Journal of Evolution Equations, 20 (4). pp. 1419-1451. ISSN 1424-3199

Giribet, Juan and Langer, Matthias and Martínez Pería, Francisco and Philipp, Friedrich and Trunk, Carsten (2020) Spectral enclosures for a class of block operator matrices. Journal of Functional Analysis, 278 (10). 108455. ISSN 0022-1236

Estrada, Ernesto and Hameed, Ehsan Mejeed and Langer, Matthias and Puchalska, Aleksandra (2018) Path Laplacian operators and superdiffusive processes on graphs. II. Two-dimensional lattice. Linear Algebra and its Applications, 555. pp. 373-397. ISSN 0024-3795

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir and Rohleder, Jonathan (2018) Spectral enclosures for non-self-adjoint extensions of symmetric operators. Journal of Functional Analysis, 275 (7). pp. 1808-1888. ISSN 0022-1236

Giribet, Juan and Langer, Matthias and Leben, Leslie and Maestripieri, Alejandra and Martinez Peria, Francisco and Trunk, Carsten (2018) Spectrum of J-frame operators. Opuscula Mathematica, 38 (5). pp. 623-649. ISSN 2300-6919

Cooper, N and Da Ros, E and Nute, J and Baldolini, D and Jouve, P and Hackermüller, L and Langer, M (2018) Collimated dual species oven source and its characterisation via spatially resolved fluorescence spectroscopy. Journal of Physics D: Applied Physics, 51 (10). 105602. ISSN 1361-6463

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir and Rohleder, Jonathan (2017) Quasi boundary triples and semibounded self-adjoint extensions. Proceedings of the Royal Society of Edinburgh: Section A Mathematics, 147 (5). pp. 895-916. ISSN 0308-2105

Estrada, Ernesto and Hameed, Ehsan and Hatano, Naomichi and Langer, Matthias (2017) Path Laplacian operators and superdiffusive processes on graphs. I. one-dimensional case. Linear Algebra and its Applications, 523. pp. 307-334. ISSN 0024-3795

Langer, Matthias and Strauss, Michael (2017) Spectral properties of unbounded J-self-adjoint block operator matrices. Journal of Spectral Theory, 7 (1). pp. 137-190. ISSN 1664-0403

Jacob, Birgit and Langer, Matthias and Trunk, Carsten (2016) Variational principles for self-adjoint operator functions arising from second order systems. Operators and Matrices, 10 (3). pp. 501-531. ISSN 1846-3886

Behrndt, J. and Langer, M. and Lotoreichik, V. (2016) Boundary triples for Schrödinger operators with singular interactions on hypersurfaces. Nanosystems: Physics, Chemistry, Mathematics, 7 (2). pp. 290-302. ISSN 2305-7971

Langer, Matthias and Strauss, Michael (2016) Triple variational principles for self-adjoint operator functions. Journal of Functional Analysis, 270 (6). pp. 2019-2047. ISSN 0022-1236

Behrndt, Jussi and Grubb, Gerd and Langer, Matthias and Lotoreichik, Vladimir (2015) Spectral asymptotics for resolvent differences of elliptic operators with δ and δ'-interactions on hypersurfaces. Journal of Spectral Theory, 5 (4). pp. 697-729. ISSN 1664-0403

Duffy, Brian R. and Langer, Matthias and Wilson, Stephen K. (2015) Closed-form solution of a thermocapillary free-film problem due to Pukhnachev. European Journal of Applied Mathematics, 26 (5). pp. 721-741. ISSN 0956-7925

Langer, Matthias and Woracek, Harald (2015) Distributional representations of Nκ(∞) -functions. Mathematische Nachrichten, 288 (10). pp. 1127-1149. ISSN 0025-584X

Tant, Katherine M.M. and Mulholland, Anthony J. and Langer, Matthias and Gachagan, Anthony (2015) A fractional Fourier transform analysis of the scattering of ultrasonic waves. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 471 (2175). 471. ISSN 1471-2962

Langer, Matthias and Woracek, Harald (2015) Stability of N-extremal measures. Methods of Functional Analysis and Topology, 21 (1). pp. 69-75. ISSN 1029-3531

Langer, Matthias and Woracek, Harald (2014) Stability of the derivative of a canonical product. Complex Analysis and Operator Theory, 8 (6). pp. 1183-1224. ISSN 1661-8254

Ibrogimov, Orif and Langer, Heinz and Langer, Matthias and Tretter, Christiane (2013) Essential spectrum of systems of singular differential equations. Acta Scientiarum Mathematicarum, 79 (3-4). pp. 423-465. ISSN 0001-6969

Banasiak, Jacek and Lamb, Wilson and Langer, Matthias (2013) Strong fragmentation and coagulation with power-law rates. Journal of Engineering Mathematics, 82 (1). pp. 199-215. ISSN 0022-0833

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir (2013) Trace formulae and singular values of resolvent power differences of self-adjoint elliptic operators. Journal of the London Mathematical Society, 88 (2). pp. 319-337. ISSN 0024-6107

Langer, Matthias and Woracek, Harald (2013) Indefinite Hamiltonian systems whose Titchmarsh–Weyl coefficients have no finite generalized poles of non-positive type. Operators and Matrices, 7 (3). pp. 477-555. ISSN 1846-3886

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir (2013) Spectral estimates for resolvent differences of self-adjoint elliptic operators. Integral Equations and Operator Theory, 77 (1). pp. 1-37. ISSN 0378-620X

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir (2013) Schrödinger operators with δ and δ′-potentials supported on hypersurfaces. Annales Henri Poincaré, 14 (2). pp. 385-423. ISSN 1424-0637

Brown, B. Malcolm and Langer, Heinz and Langer, Matthias (2013) Bessel-type operators with an inner singularity. Integral Equations and Operator Theory, 75 (2). pp. 257-300. ISSN 0378-620X

Langer, Matthias and Woracek, Harald (2013) The exponential type of the fundamental solution of an indefinite Hamiltonian system. Complex Analysis and Operator Theory, 7 (1). pp. 285-312. ISSN 1661-8254

Smith, Ann Louise and Lamb, Wilson and Langer, Matthias and McBride, Adam (2012) Discrete fragmentation with mass loss. Journal of Evolution Equations, 12 (1). pp. 181-201. ISSN 1424-3199

Da Costa, F.P. and Grinfeld, Michael and Langer, Matthias and Mottram, Nigel J. and Pinto, J.T. (2012) Kickback in nematic liquid crystals. Quarterly of Applied Mathematics, 70 (1). pp. 99-110. ISSN 0033-569X

Langer, Matthias and Woracek, Harald (2011) A local inverse spectral theorem for Hamiltonian systems. Inverse Problems, 27 (5). 055002. ISSN 0266-5611

Grinfeld, Michael and Langer, Matthias and Mottram, Nigel (2011) Nematic viscosity estimation using director kickback dynamics. Liquid Crystals, 38. pp. 981-987. ISSN 0267-8292

Langer, Matthias and Woracek, H. (2011) A function space model for canonical systems. Acta Scientiarum Mathematicarum, 77 (1-2). pp. 101-165.

Brown, B. Malcolm and Langer, M. and Marletta, M. and Tretter, C. and Wagenhofer, M. (2010) Eigenvalue enclosures and exclosures for non-self-adjoint problems in hydrodynamics. LMS Journal of Computation and Mathematics, 13. pp. 65-81. ISSN 1461-1570

Behrndt, Jussi and Langer, Matthias (2010) On the adjoint of a symmetric operator. Journal of the London Mathematical Society, 82 (3). pp. 563-580.

Behrndt, J. and Langer, M. and Lobanov, I. and Lotoreichik, V. and Popov, I. Yu. (2010) A remark on Schatten-von Neumann properties of resolvent differences of generalized Robin Laplacians on bounded domains. Journal of Mathematical Analysis and Applications, 371 (2). pp. 750-758. ISSN 0022-247X

Langer, M. and Woracek, Harald (2009) Dependence of the Weyl coefficient on singular interface conditions. Proceedings of the Edinburgh Mathematical Society, 52 (2). pp. 445-487. ISSN 0013-0915

Langer, M. and Langer, Heinz and Markus, Alexander and Tretter, Christiane (2008) The Virozub-Matsaev condition and spectrum of definite type for self-adjoint operator functions. Complex Analysis and Operator Theory, 2 (1). pp. 99-134. ISSN 1661-8254

Behrndt, Jussi and Langer, M. (2007) Boundary value problems for elliptic partial differential operators on bounded domains. Journal of Functional Analysis, 243 (2). pp. 536-565. ISSN 0022-1236

Langer, M. and Tretter, Christiane (2006) Variational principles for eigenvalues of the Klein-Gordon equation. Journal of Mathematical Physics, 47 (10). 103506. ISSN 0022-2488

Langer, M. (2006) A general HELP inequality connected with symmetric operators. Proceedings A: Mathematical, Physical and Engineering Sciences, 462 (2066). pp. 587-606. ISSN 1471-2962

Langer, Heinz and Langer, Matthias and Markus, Alexander and Tretter, Christiane (2005) Spectrum of definite type of self-adjoint operators in Krein spaces. Linear and Multilinear Algebra, 53 (2). pp. 115-136. ISSN 0308-1087

Brown, B.Malcolm and Langer, M. and Marletta, Marco (2004) Spectral concentrations and resonances of a second order block operator matrix and an associated λ-rational Sturm-Liouville problem. Proceedings A: Mathematical, Physical and Engineering Sciences, 460 (2052). pp. 3403-3420. ISSN 1471-2962

Kraus, Margarita and Langer, M. and Tretter, Christiane (2004) Variational principles and eigenvalue estimates for unbounded block operator matrices and applications. Journal of Computational and Applied Mathematics, 171 (1-2). pp. 311-334. ISSN 0377-0427

Eschwe, D. and Langer, M. (2004) Variational principles for eigenvalues of self-adjoint operator functions. Integral Equations and Operator Theory, 49 (3). pp. 287-321. ISSN 0378-620X

Langer, Heinz and Langer, Matthias and Sasvári, Zoltán (2004) Continuations of Hermitian indefinite functions and corresponding canonical systems : an example. Methods of Functional Analysis and Topology, 10 (1). pp. 39-53. ISSN 1029-3531

Brown, B.M. and Langer, M. and Marletta, M. and Tretter, C. and Wagenhofer, M. (2003) Eigenvalue bounds for the singular Sturm–Liouville problem with a complex potential. Journal of Physics A: Mathematical and Theoretical, 36 (13). 3773. ISSN 0305-4470

Langer, Matthias and Woracek, Harald (2002) A characterization of intermediate Weyl coefficients. Monatshefte für Mathematik, 135 (2). pp. 137-155. ISSN 0026-9255

Langer, H. and Langer, M. and Tretter, Christiane (2002) Variational principles for eigenvalues of block operator matrices. Indiana University Mathematics Journal, 51 (6). pp. 1427-1460. ISSN 0022-2518

Langer, Matthias (2001) Resonances of a λ-rational Sturm–Liouville problem. Proceedings of the Royal Society of Edinburgh: Section A Mathematics, 131 (3). pp. 709-720. ISSN 0308-2105

Adamjan, V. and Langer, Heinz and Langer, M. (2001) A spectral theory for a λ-rational Sturm-Liouville problem. Journal of Differential Equations, 171 (2). pp. 315-345. ISSN 0022-0396

Langer, Matthias (2000) Eigenvalues of a λ-rational Sturm–Liouville problem. Mathematische Nachrichten, 210 (1). pp. 163-176. ISSN 0025-584X

Book Section

Langer, Matthias and Woracek, Harald; Binder, Ilia and Kinzebulatov, Damir and Mashreghi, Javad, eds. (2023) Direct and inverse spectral theorems for a class of canonical systems with two singular endpoints. In: Function Spaces, Theory and Applications. Fields Institute Communications . Springer, Cham, Switzerland, pp. 105-205. ISBN 9783031392702

Behrndt, Jussi and Langer, Matthias and Lotoreichik, Vladimir; Dittrich, Jaroslav and Kovarik, Hynek and Laptev, Ari, eds. (2017) Trace formulae for Schrödinger operators with singular interactions. In: Functional Analysis and Operator Theory for Quantum Physics. EMS Series of Congress Reports . European Mathematical Society, Switzerland, pp. 129-152. ISBN 9783037196755

Behrndt, Jussi and Langer, Matthias; Hassi, Seppo and de Snoo, Hendrik S. V. and Szafraniec, Franciszek Hugon, eds. (2012) Elliptic operators, Dirichlet-to-Neumann maps and quasi boundary triples. In: Operator Methods for Boundary Value Problems. London Mathematial Society Lecture Note Series . Cambridge University Press, pp. 121-160. ISBN 9781107606111

Langer, M. and Luger, A.; Behrndt, Jussi and Förster, Karl-Heinz and Trunk, Carsten, eds. (2010) On norms in indefinite product spaces. In: Recent Advances in Operator Theory in Hilbert and Krein Spaces. Operator Theory: Advances and Applications, 198 . Birkhäuser, pp. 259-264. ISBN 978-3-0346-0179-5

Brown, B. Malcolm and Langer, Matthias and Schmidt, Karl Michael; Exner, Pavel and Keating, Jonathan P. and Kutchment, Peter and Sunada, Toshikazu and Teplyaev, Alexander, eds. (2008) The HELP inequality on trees. In: Analysis on graphs and its applications. Proceedings of Symposia in Pure Mathematics, 77 . American Mathematical Society, pp. 337-354. ISBN 0821844717

Langer, Matthias and Luger, Annemarie; Förster, Karl-Heinz and Langer, Heinz and Jonas, Peter, eds. (2006) Scalar generalized nevanlinna functions : realizations with block operator matrices. In: Operator theory in Krein spaces and nonlinear eigenvalue problems. Operator Theory: Advances and Applications . Birkhäuser, pp. 253-276. ISBN 9783764374525