@article{HarutjunjanSchulze2006, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {The relative index for corner singularities}, issn = {0378-620X}, doi = {10.1007/s00020-005-1367-3}, year = {2006}, abstract = {We study pseudo-differential operators on a cylinder R x B where B has conical singularities. Configurations of that kind are the local model of corner singularities with cross section B. Operators in our calculus are assumed to have symbols a which are meromorphic in the complex covariable with values in the algebra of all cone operators on B. We show an explicit formula for solutions of the homogeneous equation if a is independent of the axial variable t is an element of R. Each non-bijectivity point of the symbol in the complex plane corresponds to a finite-dimensional space of solutions. Moreover, we give a relative index formula}, language = {en} } @book{HarutjunjanSchulze2005, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Conormal symbols of mixed elliptic problems with singular interfaces}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {18 S.}, year = {2005}, language = {en} } @article{HarutjunjanSchulze2005, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Boundary problems with meromorphic symbols in cylindrical domains}, issn = {0170-4214}, year = {2005}, abstract = {We show relative index formulas for boundary value problems in cylindrical domains and Sobolev spaces with different weights at too. The amplitude functions are meromorphic in the axial covariable and take values in the space of boundary value problems on the cross section of the cylinder. Copyright (c) 2005 John Wiley \& Sons, Ltd}, language = {en} } @book{HarutjunjanSchulze2006, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Boundary value problems in weighted edge spaces}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {21 S.}, year = {2006}, language = {en} } @book{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Boundary problems with meromorphic symbols in cylindrical domains}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {19 S.}, year = {2004}, language = {en} } @book{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {The zaremba problem with singular interfaces as a corner boundary value problem}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {48 S.}, year = {2004}, language = {en} } @article{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Reduction of orders in boundary value problems without transmission property}, issn = {0025-5645}, year = {2004}, abstract = {Given an algebra of pseudo-differential operators on a manifold, an elliptic element is said to be a reduction of orders, if it induces isomorphisms of Sobolev spaces with a corresponding shift of smoothness. Reductions of orders on a manifold with boundary refer to boundary value problems. We employ specific smooth symbols of arbitrary real orders and with parameters, and we show that the associated operators induce isomorphisms between Sobolev spaces on a given manifold with boundary. Such operators for integer orders have the transmission property and belong to the calculus of Boutet de Monvel [1], cf. also [9]. In general, they fit to the algebra of boundary value problems without the transmission property in the sense of [17] and [24]. Order reducing elements of the present kind are useful for constructing parametrices of mixed elliptic problems. We show that order reducing symbols have the Volterra property and are parabolic of anisotropy 1; analogous relations are formulated for arbitrary anisotropies. We then investigate parameter-dependent operators, apply a kernel cut-off construction with respect to the parameter and show that corresponding holomorphic operator-valued Mellin symbols reduce orders in weighted Sobolev spaces on a cone with boundary. We finally construct order reducing operators on a compact manifold with conical singularities and boundary}, language = {en} } @article{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Parametrices of mixed elliptic problems}, issn = {0025-584X}, year = {2004}, abstract = {Mixed elliptic problems for differential operators A in a domain Q with smooth boundary Y are studied in the form Au = f in Omega, T+/-u = g+/- on Y+/-, where Y+/- subset of Y are manifolds with a common boundary Z, such that Y- boolean OR Y+ = Y and Y- boolean AND Y+ = z, with boundary conditions T+/- on Y+/- (with smooth coefficients up to Z from the respective side) satisfying the Shapiro-Lopatinskij condition. We consider such problems in standard Sobolev spaces and characterise natural extra conditions on the interface Z with an analogue of Shapiro-Lopatinskij ellipticity for an associated transmission problem on the boundary; then the extended operator is Fredholm. The transmission operators on the boundary with respect to Z belong to a complete pseudo-differential calculus, a modification of the algebra of boundary value problems without the transmission property. We construct parametrices of elliptic elements in that calculus, and we obtain parametrices of the original mixed problems under additional conditions on the interface. We consider the Zaremba problem and other mixed problems for the Laplace operator, determine the number of extra conditions and calculate the index of associated Fredholm operators. (C) 2004 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim}, language = {en} } @book{DinesHarutjunjanSchulze2003, author = {Dines, Nicoleta and Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {The Zaremba problem in edge sobolev spaces}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {38 S.}, year = {2003}, language = {en} } @book{HarutjunjanSchulze2002, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Reduction of Orders in Boundary Value Problems without the Transmission Proberty}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {23 S.}, year = {2002}, language = {en} } @unpublished{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Boundary problems with meromorphic symbols in cylindrical domains}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26735}, year = {2004}, abstract = {We show relative index formulas for boundary value problems in cylindrical domains and Sobolev spaces with different weigths at ±∞. The amplitude functions are meromorphic in the axial covariable and take values in the space of boundary value problems on the cross section of the cylinder.}, language = {en} } @book{HarutjunjanSchulze2002, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Asymptotics and relative index on a cylinder with conical cross section}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {45 S.}, year = {2002}, language = {en} } @book{HarutjunjanSchulze2001, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Mixed problems and edge calculus : symbol structures}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {43 S.}, year = {2001}, language = {en} } @book{HarutjunjanSchulzeWitt2000, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang and Witt, Ingo}, title = {Boundary value problems in the edge pseudo-differential calculus}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell}, publisher = {Univ.}, address = {Potsdam}, issn = {1437-739X}, pages = {48 S.}, year = {2000}, language = {en} } @unpublished{HarutjunjanSchulze2002, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {Asymptotics and relative index on a cylinder with conical cross section}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26446}, year = {2002}, abstract = {We study pseudodifferential operators on a cylinder IR x B with cross section B that conical singularities. Configurations of that kind are the local model of cornere singularities with base spaces B. Operators A in our calculus are assumed to have symbols α which are meromorphic in the complex covariable with values in the space of all cone operators on B. In case α is dependent of the axial variable t ∈ IR, we show an explicit formula for solutions of the homogeneous equation. Each non-bjectivity point of the symbol in the complex plane corresponds to a finite-dimensional space of solutions. Moreover, we give a relative index formula.}, language = {en} } @unpublished{DinesHarutjunjanSchulze2003, author = {Dines, Nicoleta and Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {The Zaremba problem in edge Sobolev spaces}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26615}, year = {2003}, abstract = {Mixed elliptic boundary value problems are characterised by conditions which have a jump along an interface of codimension 1 on the boundary. We study such problems in weighted edge Sobolev spaces and show the Fredholm property and the existence of parametrices under additional conditions of trace and potential type on the interface. Our methods from the calculus of boundary value problems on a manifold with edges will be illustrated by the Zaremba problem and other mixed problems for the Laplace operator.}, language = {en} } @unpublished{HarutjunjanSchulze2004, author = {Harutjunjan, Gohar and Schulze, Bert-Wolfgang}, title = {The Zaremba problem with singular interfaces as a corner boundary value problem}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26855}, year = {2004}, abstract = {We study mixed boundary value problems for an elliptic operator A on a manifold X with boundary Y , i.e., Au = f in int X, T±u = g± on int Y±, where Y is subdivided into subsets Y± with an interface Z and boundary conditions T± on Y± that are Shapiro-Lopatinskij elliptic up to Z from the respective sides. We assume that Z ⊂ Y is a manifold with conical singularity v. As an example we consider the Zaremba problem, where A is the Laplacian and T- Dirichlet, T+ Neumann conditions. The problem is treated as a corner boundary value problem near v which is the new point and the main difficulty in this paper. Outside v the problem belongs to the edge calculus as is shown in [3]. With a mixed problem we associate Fredholm operators in weighted corner Sobolev spaces with double weights, under suitable edge conditions along Z \ {v} of trace and potential type. We construct parametrices within the calculus and establish the regularity of solutions.}, language = {en} }