Sökning: "Perturbation"

Visar resultat 1 - 5 av 437 avhandlingar innehållade ordet Perturbation.

  1. 1. Finite perturbation : configuration interaction calculations of nuclear magnetic resonance spin-spin coupling constants

    Författare :Aatto Laaksonen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : .... LÄS MER

  3. 2. Multiconfigurational perturbation theory

    Författare :Kerstin Andersson; Karlstads universitet; []
    Nyckelord :Electron correlation; CASSCF; multiconfigurational second-order perturbation theory; CASPT2; ozone; C; N; O; F; Si; P; S; Cl; Ni; benzene; pyridine; pyrazine; pyrimidine; pyridazine; s-triazine; electric properties; excited states; spectroscopic data;

    Sammanfattning : The aim of the thesis is to analyze a method which describes the electron correlation in atoms and molecules. The method is based on Rayleigh-Schrödinger perturbation theory with a partitioning of the Hamiltonian into a fairly simple zeroth-order operator and a perturbation operator. LÄS MER

  4. 3. Topics in perturbation theory : From IBP identities to integrands

    Författare :Alessandro Georgoudis; Joseph A. Minahan; Tristan McLoughlin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Perturbation theory; Feynman Integrals; Integrable field theories; Correlation functions.; Theoretical Physics; Teoretisk fysik;

    Sammanfattning : In this thesis we present different topics in perturbation theory. We start by introducing the method of integration by parts identities, which reduces a generic Feynman integral to a linear combination of a finite basis of master integrals. LÄS MER

  5. 4. The Powers of Perturbation Theory : Loops and Gauge Invariance in Particle Physics

    Författare :Johan Löfgren; Rikard Enberg; Kimmo Kainulainen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Beyond the Standard Model; Electroweak phase transition; Perturbation theory; High Energy Physics; Högenergifysik;

    Sammanfattning : The Standard Model is the best particle physics theory we have, but there are still phenomena that it cannot explain. In this thesis I have worked on two different projects that connect to two of the biggest unsolved questions of the Standard Model. LÄS MER

  7. 5. The flight perturbation problem : operational aircraft rescheduling

    Författare :Tobias Andersson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : When there is a perturbation in a carefully planned flight schedule, e.g. an aircraft breakdown, it is important to minimize the negative consequences of this disturbance. In this thesis, a model and a number of solution strategies for the Flight Perturbation Problem is presented. LÄS MER