Search for dissertations about: "pseudodifferential operator"

Found 5 swedish dissertations containing the words pseudodifferential operator.

2. 1. Resonances of Dirac Operators

   Author : Jimmy Kungsman; Wolfgang Staubach; Roman Schubert; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Semiclassical analysis; Dirac operator; resonances; Poisson trace formula; scattering theory; complex absorbing potential; pseudodifferential operator; Mathematics; Matematik;

   Abstract : This thesis consists of a summary of four papers dealing with resonances of Dirac operators on Euclidean 3-space. In Paper I we show that the Complex Absorbing Potential (CAP) method is valid in the semiclassical limit for resonances sufficiently close to the real line if the potential is smooth and compactly supported. READ MORE

4. 2. New weighted inequalities with applications to pseudodifferential operators

   Author : Stefan Eilertsen; Per-Anders Ivert; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Weighted integral inequalities; fractional Laplacian; Dirichlet problem; behavior near the boundary; special functions;

   Abstract : This thesis is devoted to weighted integral inequalities and their applications to the  study of boundary behavior of solutions to Dirichlet's problem for fractional powers of the Laplacian.We obtain a necessary and sufficient condition on μ for the operator (—Δ)μin R 0 , 0 ... READ MORE

5. 3. On time-frequency analysis and pseudo-differential operators for vector-valued functions

   Author : Patrik Wahlberg; Joachim Toft; Luigi Rodino; Växjö universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

   Abstract : This thesis treats different aspects of time-frequency analysis and pseudodifferential operators, with particular emphasis on techniques involving vector-valued functions and operator-valued symbols. The vector (Banach) space is either motivated by an application as in Paper I, where it is a space of stochastic variables, or is part of a general problem as in Paper II, or arises naturally from problems for scalar-valued operators and function spaces, as in Paper V. READ MORE

6. 4. Simple Layer Potentials on Lipschitz Surfaces: An Asymptotic Approach

   Author : Johan Thim; Vladimir Kozlov; Bengt Ove Turesson; Martin Costabel; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Singular integrals; Lipschitz surfaces; Mathematical analysis; Analys;

   Abstract : This work is devoted to the equationwhere S is the graph of a Lipschitz function φ on RN with small Lipschitz constant, and dS is the Euclidian surface measure. The integral in the left-hand side is referred to as a simple layer potential and f is a given function. READ MORE

7. 5. Properties of wave-front sets and non-tangential convergence

   Author : Karoline Johansson; Joachim Toft; Luigi Rodino; Linnéuniversitetet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fourier Banach spaces; Generalized free time-dependent Schrödinger equation; Micro-local; Modulation spaces; Non-tangential convergence; Pseudo-differential operators; Regularity; Wave-front sets.; Mathematical analysis; Analys; Matematik; Mathematics;

   Abstract : In this thesis we consider regularity properties for solutions to partial differential equations and pseudo-differential equations. The thesis mainly concerns wave-front sets and micro-local properties. READ MORE