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Operators of Fuchs type, conical singularities, and asymptotic methods
This text is a revised version of the authors Habilitationsschrift which was submitted to the University of Augsburg, 1993. Fuchs type differential operators are used to model the analysis onExpand
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Unbounded Fredholm Operators and Spectral Flow
Abstract We study the gap (= “projection norm” = “graph distance”) topology of the space of all (not necessarily bounded) self-adjoint Fredholm operators in a separable Hilbert space by the CayleyExpand
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Evolution and structure of magnetic fields in simulated galaxy clusters
We use cosmological magneto-hydrodynamic simulations to study the evolution of magnetic elds in galaxy clusters in two dierent cosmological models, a standard-CDM and a -CDM model. We show that theExpand
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On the Noncommutative Residue for Pseudodifferential Operators with log-Polyhomogeneous Symbols
AbstractWe study various aspects of the noncommutative residue for an algebra of pseudodifferential operators whose symbols have an expansion $$a \sim \sum\limits_{j = 0}^\infty {a_{m - j,} } a_{m -Expand
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The uniqueness of the spectral flow on spaces of unbounded self--adjoint Fredholm operators
We discuss several natural metrics on spaces of unbounded self--adjoint operators and their relations, among them the Riesz and the graph metric. We show that the topologies of the spaces of FredholmExpand
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On the deficiency indices and self-adjointness of symmetric Hamiltonian systems
Abstract The main purpose of this paper is to investigate the formal deficiency indices N ± of a symmetric first-order system Jf′+Bf=λ H f on an interval I, where I= R or I= R ± . Here J,B, H are n×nExpand
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A local global principle for regular operators in Hilbert C⁎-modules
Abstract Hilbert C ⁎ -modules are the analogues of Hilbert spaces where a C ⁎ -algebra plays the role of the scalar field. With the advent of Kasparovʼs celebrated KK -theory they became a standardExpand
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Spectral flow and the unbounded Kasparov product
Abstract We present a fairly general construction of unbounded representatives for the interior Kasparov product. As a main tool we develop a theory of C 1 -connections on operator ⁎-modules; we doExpand
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We consider a regular singular Sturm-Liouville operator on the line segment (0,1]. We impose certain boundary conditions such that we obtain a semi-bounded self-adjoint operator.Expand
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The eta-invariant, Maslov index, and spectral flow for Dirac-type operators on manifolds with boundary
Several proofs have been published of the Mod Z gluing formula for the eta-invariant of a Dirac operator. However, so far the integer contribution to the gluing formula for the eta-invariant is leftExpand
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