Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Combinatorial Methods in Complex Analysis

    Författare :Per Alexandersson; Boris Shapiro; Alexandre Eremenko; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; combinatorics; Schrödinger equation; Toeplitz matrix; sums of squares; Schur polynomials; Mathematics; matematik;

    Sammanfattning : The theme of this thesis is combinatorics, complex analysis and algebraic geometry. The thesis consists of six articles divided into four parts.Part A: Spectral properties of the Schrödinger equationThis part consists of Papers I-II, where we study a univariate Schrödinger equation with a complex polynomial potential. LÄS MER

  3. 2. Multiplier Sequences for Laguerre bases

    Författare :Elin Ottergren; Petter Brändén; Björn Gustafsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stability preserving operator; orthogonal polynomials; multiplier sequences; Mathematics; matematik;

    Sammanfattning : Pólya and Schur completely characterized all real-rootedness preserving linear operators acting on the standard monomial basis in their famous work from 1914. The corresponding eigenvalues are from then on known as multiplier sequences. LÄS MER

  4. 3. Extreme points of the Vandermonde determinant in numerical approximation, random matrix theory and financial mathematics

    Författare :Asaph Keikara Muhumuza; Sergei Silvestrov; Anatoliy Malyarenko; Karl Lundengård; Milica Rancic; Olga Liivapuu; Mälardalens högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mathematics Applied Mathematics; matematik tillämpad matematik;

    Sammanfattning : This thesis discusses the extreme points of the Vandermonde determinant on various surfaces, their applications in numerical approximation, random matrix theory and financial mathematics. Some mathematical models that employ these extreme points such as curve fitting, data smoothing, experimental design, electrostatics, risk control in finance and method for finding the extreme points on certain surfaces are demonstrated. LÄS MER

  5. 4. Quantum many-body systems exactly solved by special functions

    Författare :Martin Hallnäs; Edwin Langmann; Pavel Winternitz; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum many-body systems; integrable systems; special functions; Mathematical physics; Matematisk fysik;

    Sammanfattning : This thesis concerns two types of quantum many-body systems in one dimension exactly solved by special functions: firstly, systems with interactions localised at points and solved by the (coordinate) Bethe ansatz; secondly, systems of Calogero-Sutherland type, as well as certain recently introduced deformations thereof, with eigenfunctions given by natural many-variable generalisations of classical (orthogonal) polynomials. The thesis is divided into two parts. LÄS MER