Sökning: "semiclassical physics"

Hittade 4 uppsatser innehållade orden semiclassical physics.

  1. 1. The black hole information paradox and holography

    Master-uppsats, Uppsala universitet/Teoretisk fysik

    Författare :Ona Mola Bertran; [2023]
    Nyckelord :information paradox; semiclassical physics; holography; AdS CFT correspondence; island formula; entanglement entropy;

    Sammanfattning : Hawking theorized in 1974 that black holes emit particles as a quantum effect. It follows from this fact that a black hole that emits particles while absorbing none ends up evaporating. The process of black hole evaporation studied from semiclassical gravity violates quantum mechanics leading to serious problems. LÄS MER

  3. 2. The effect of disorder on the axial anomaly in a lattice model in 1 + 1 dimensions

    Master-uppsats, KTH/Fysik

    Författare :Agnes Wattrang; [2023]
    Nyckelord :Axial anomaly; tight-binding model; semiclassical physics; correlated disorder.; Axial kiral anomali; tätbindningsmodell; semiklassisk fysik; korrelerad oordning;

    Sammanfattning : This work investigates the effect of a disorder potential, that represents impurities/dislocations in the lattice, on the time-dependent signature of the axial anomaly in a one-band tight-binding model in one spatial dimension. The tight-binding model is solved numerically and the simulation results are compared with a semiclassical expression for the time-dependent axial density, n5(t), due to Nielsen and Ninomiya [1]. LÄS MER

  4. 3. Comparing Quantum and Semi-Classical Approaches to Non-Collinear Magnetism in an Electron-Spin Dimer

    Kandidat-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Matematisk fysik

    Författare :Sherwan Jamo Abdi; [2023]
    Nyckelord :Skyrmion Electron Spin Dzyaloshinskii-Moriya Interaction DMI Ehrenfest Semiclassical; Physics and Astronomy;

    Sammanfattning : In this bachelor thesis, an explorative theoretical analysis is presented on a model system characterized by various and competing magnetic interactions. The system comprises two localized magnetic moments (spins), and a single itinerant electron that hops between two orbitals located at the spins’ positions. LÄS MER

  5. 4. Microscopic and Macroscopic Samples of Atoms in Superposition States Studied by Attosecond Pulses

    Magister-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

    Författare :Axel Stenquist; [2021]
    Nyckelord :Mathematical physics; Theoretical physics; Atomic physics; Attosecond physics; Ultra-fast physics; Numerical simulations; Microscopic; Mesoscopic; Macroscopic; Superposition; Light matter interaction; Quantum mechanics; Electromagnetism; Semiclassical; Attosecond transient absorption spectroscopy; ATAS; Förster resonance; FRET; Two-atom model; Inter-atomic interaction; Dipole-dipole interaction; Many-atom model; Collective coherent effects; Time-dependent configuration-interaction singles; TDCIS; Physics and Astronomy;

    Sammanfattning : In the present thesis, the interaction between atoms in superposition states and attosecond pulses is studied from the microscopic to the macroscopic regime. Using a semi-classical framework, three different models have been explored in order to investigate attosecond light--matter interaction processes. LÄS MER