Sökning: "egenvärdesproblem"

Hittade 4 uppsatser innehållade ordet egenvärdesproblem.

  1. 1. Phase Diagrams of Finite Spin Chains with Coupled Spin and Lattice Vibrations

    Kandidat-uppsats, Uppsala universitet/Materialteori

    Författare :Siri Alva Berge; [2021]
    Nyckelord :spin-lattice coupling; spin-vibration coupling; Heisenberg exchange; magnetism;

    Sammanfattning : The spin-lattice coupling is due to itinerant electrons interacting with both spins of ions and phonons, mediating a coupling between magnetic spin moments and lattice vibrations. In this project, the coupling is studied systematically for finite quantum spin chains of size 2 – 10. LÄS MER

  3. 2. A numerical investigation of Anderson localization in weakly interacting Bose gases

    Master-uppsats, KTH/Numerisk analys, NA

    Författare :Crystal Ugarte; [2020]
    Nyckelord :Applied mathematics; finite elements; eigenvalue solver; eigenvalue problem; Bose-Einstein Codensate; Finita elementmetoden; tillämpad matematik; Bose-Einstein kondensat; egenvärdesalgoritm; egenvärdesproblem;

    Sammanfattning : The ground state of a quantum system is the minimizer of the total energy of that system. The aim of this thesis is to present and numerically solve the Gross-Pitaevskii eigenvalue problem (GPE) as a physical model for the formation of ground states of dilute Bose gases at ultra-low temperatures in a disordered potential. LÄS MER

  4. 3. Evaluation of methods for quantifying returns within the premium pension

    Master-uppsats, KTH/Matematisk statistik

    Författare :Emil Backman; David Petersson; [2020]
    Nyckelord :Pension; internal rate of return; applied mathematics; big matrix; numerical methods; large eigenvalue problem; finance; risk analysis; extreme value modeling; probability; stochastic modeling; Pension; intern ränta; tillämpad matematik; stora matrismetoder; numeriska metoder; stora egenvärdesproblem; finans; riskanalys; modellering av extrema värden; sannolikhet; stokastisk modellering;

    Sammanfattning : Pensionsmyndigheten's (the Swedish Pensions Agency) current calculation of the internal rate of return for 7.7 million premium pension savers is both time and resource consuming. LÄS MER

  5. 4. Computation of Eigenmodes in Three-Dimensional Structures

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Daniel Lilja; Olof Hummelgren; [2020]
    Nyckelord :;

    Sammanfattning : In this thesis the eigenmodes and eigenvalues of three dimensional structures are analyzed using the Python environment FEniCS in combination with an implementation of the Arnoldi method in MATLAB for calculation of eigenpairs. This is done by considering separable solutions of the wave equation and subsequently expressing these as the solutions to an eigenvalue problem. LÄS MER