Sökning: "Schrödinger operator"
Visar resultat 16 - 20 av 23 avhandlingar innehållade orden Schrödinger operator.
16. Selected Topics in Partial Differential Equations
Sammanfattning : This Ph.D. thesis consists of five papers and an introduction to the main topics of the thesis. In Paper I we give an abstract criteria for existence of multiple solutions to nonlinear coupled equations involving magnetic Schrödinger operators. LÄS MER
17. On direct and inverse scattering problems in dimension one
Sammanfattning : Direct and inverse scattering problems for the Schrödinger operator in dimension one are investigated. Relations between the scattering problems defined by regular and zero range potentials are investigated.Correct mathematical definition of the «^'-interaction is introduced and investigated in detail. LÄS MER
18. On Supersingular Perturbations
Sammanfattning : This thesis consists of four papers and deals with supersingular rank one perturbations of self-adjoint operators and their models in Hilbert or Pontryagin spaces. Here, the term supersingular describes perturbation elements that are outside the underlying space but still obey a certain regularity conditions. LÄS MER
19. Multiconfigurational perturbation theory
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
20. Asymptotic and universal spectral estimates with applications in many-body quantum mechanics and spectral shape optimization
Sammanfattning : This thesis consists of eight papers primarily concerned with the quantitative study of the spectrum of certain differential operators. The majority of the results split into two categories. LÄS MER
