@unpublished{Karp2006, author = {Karp, Lavi}, title = {On null quadrature domains}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30156}, year = {2006}, abstract = {The characterization of null quadrature domains in Rn (n ≥ 3) has been an open problem throughout the past two and a half decades. A substantial contribution was done by Friedman and Sakai [10]; they showed that if the complement is bounded, then null quadrature domains are exactly the complement of ellip- soids. The first result with unbounded complements appeared in [15], there it is assumed the complement is contained in an infinitely cylinder. The aim of this paper is to show the relation between null quadrature domains and Newton's theorem on the gravitational force induced by homogeneous homoeoidal ellipsoids. We also succeed to make progress in the classification problem and we show that if the boundary of null quadrature domain is contained in a strip and the complement satisfies a certain capacity condition at infinity, then it must be a half-space or a complement of a strip. In addition, we present a Phragm\Pen-Lindel{\"o}f type theorem which seems to be forgotten in the literature.}, language = {en} } @unpublished{BrauerKarp2006, author = {Brauer, Uwe and Karp, Lavi}, title = {Local existence of classical solutions for the Einstein-Euler system using weighted Sobolev spaces of fractional order}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30175}, year = {2006}, abstract = {We prove the existence of a class of local in time solutions, including static solutions, of the Einstein-Euler system. This result is the relativistic generalisation of a similar result for the Euler-Poisson system obtained by Gamblin [8]. As in his case the initial data of the density do not have compact support but fall off at infinity in an appropriate manner. An essential tool in our approach is the construction and use of weighted Sobolev spaces of fractional order. Moreover, these new spaces allow us to improve the regularity conditions for the solutions of evolution equations. The details of this construction, the properties of these spaces and results on elliptic and hyperbolic equations will be presented in a forthcoming article.}, language = {en} } @unpublished{Tarkhanov2006, author = {Tarkhanov, Nikolai Nikolaevich}, title = {Euler characteristic of Fredholm quasicomplexes}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30117}, year = {2006}, abstract = {By quasicomplexes are usually meant perturbations of complexes small in some sense. Of interest are not only perturbations within the category of complexes but also those going beyond this category. A sequence perturbed in this way is no longer a complex, and so it bears no cohomology. We show how to introduce Euler characteristic for small perturbations of Fredholm complexes. The paper is to appear in Funct. Anal. and its Appl., 2006.}, language = {en} } @unpublished{Paneah2006, author = {Paneah, Boris}, title = {Another approach to the stability of linear functional operators}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30139}, year = {2006}, abstract = {Contents: 1 Introduction. 2 The main notations and notions. 3 Statement of results 4 Proofs of the main results.}, language = {en} } @unpublished{ChenWu2006, author = {Chen, Hua and Wu, Shaohua}, title = {On existence of solutions for some hyperbolic-parabolic type chemotaxis systems}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30082}, year = {2006}, abstract = {In this paper, we discuss the local and global existence of week solutions for some hyperbolic-parabolic systems modelling chemotaxis.}, language = {en} } @unpublished{GilKrainerMendoza2006, author = {Gil, Juan B. and Krainer, Thomas and Mendoza, Gerardo A.}, title = {On rays of minimal growth for elliptic cone operators}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30064}, year = {2006}, abstract = {We present an overview of some of our recent results on the existence of rays of minimal growth for elliptic cone operators and two new results concerning the necessity of certain conditions for the existence of such rays.}, language = {en} } @unpublished{MaergoizTarkhanov2006, author = {Maergoiz, L. and Tarkhanov, Nikolai Nikolaevich}, title = {Optimal recovery from a finite set in Banach spaces of entire functions}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30199}, year = {2006}, abstract = {We develop an approach to the problem of optimal recovery of continuous linear functionals in Banach spaces through information on a finite number of given functionals. The results obtained are applied to the problem of the best analytic continuation from a finite set in the complex space Cn, n ≥ 1, for classes of entire functions of exponential type which belong to the space Lp, 1 < p < 1, on the real subspace of Cn. These latter are known as Wiener classes.}, language = {en} } @unpublished{Gosson2006, author = {Gosson, Maurice A. de}, title = {Symplectic geometry, Wigner-Weyl-Moyal calculus, and quantum mechanics in phase space}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30212}, year = {2006}, abstract = {Contents: Part I: Symplectic Geometry Chapter 1: Symplectic Spaces and Lagrangian Planes Chapter 2: The Symplectic Group Chapter 3: Multi-Oriented Symplectic Geometry Chapter 4: Intersection Indices in Lag(n) and Sp(n) Part II: Heisenberg Group, Weyl Calculus, and Metaplectic Representation Chapter 5: Lagrangian Manifolds and Quantization Chapter 6: Heisenberg Group and Weyl Operators Chapter 7: The Metaplectic Group Part III: Quantum Mechanics in Phase Space Chapter 8: The Uncertainty Principle Chapter 9: The Density Operator Chapter 10: A Phase Space Weyl Calculus}, language = {en} } @unpublished{MakhmudovNiyozovTarkhanov2006, author = {Makhmudov, O. and Niyozov, I. and Tarkhanov, Nikolai Nikolaevich}, title = {The cauchy problem of couple-stress elasticity}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30078}, year = {2006}, abstract = {We study the Cauchy problem for the oscillation equation of the couple-stress theory of elasticity in a bounded domain in R3. Both the displacement and stress are given on a part S of the boundary of the domain. This problem is densely solvable while data of compact support in the interior of S fail to belong to the range of the problem. Hence the problem is ill-posed which makes the standard calculi of Fourier integral operators inapplicable. If S is real analytic the Cauchy-Kovalevskaya theorem applies to guarantee the existence of a local solution. We invoke the special structure of the oscillation equation to derive explicit conditions of global solvability and an approximation solution.}, language = {en} } @unpublished{KrupchykTarkhanovTuomela2006, author = {Krupchyk, K. and Tarkhanov, Nikolai Nikolaevich and Tuomela, J.}, title = {Elliptic quasicomplexes in Boutet de Monvel algebra}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30122}, year = {2006}, abstract = {We consider quasicomplexes of Boutet de Monvel operators in Sobolev spaces on a smooth compact manifold with boundary. To each quasicomplex we associate two complexes of symbols. One complex is defined on the cotangent bundle of the manifold and the other on that of the boundary. The quasicomplex is elliptic if these symbol complexes are exact away from the zero sections. We prove that elliptic quasicomplexes are Fredholm. As a consequence of this result we deduce that a compatibility complex for an overdetermined elliptic boundary problem operator is also Fredholm. Moreover, we introduce the Euler characteristic for elliptic quasicomplexes of Boutet de Monvel operators.}, language = {en} }