Sökning: "NATURAL SCIENCES Physics Other physics Mathematical physics"

Visar resultat 21 - 25 av 152 avhandlingar innehållade orden NATURAL SCIENCES Physics Other physics Mathematical physics.

  1. 21. Yang-Mills Theory in Gauge-Invariant Variables and Geometric Formulation of Quantum Field Theories

    Författare :Sergey Slizovskiy; Antti Niemi; Andrey Losev; Andrey Marshakov; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Yang-Mills theory; spin-charge separation; Kaluza-Klein theory; branes; curved beta-gamma systems; Mathematical physics; Matematisk fysik; Theoretical Physics; Teoretisk fysik;

    Sammanfattning : In Part I we are dealing with effective description of Yang-Mills theories based on gauge-invarint variables. For pure Yang-Mills we study the spin-charge separation varibles. The dynamics in these variables resembles the Skyrme-Faddeev model. LÄS MER

  3. 22. Resonant Tunneling in Laterally Confined Quantum Structures

    Författare :Boel Gustafson; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gravitation; relativity; quantum mechanics; classical mechanics; Mathematical and general theoretical physics; Fysik; Physics; High peak-to-valley ratio; Lateral confinement; Quantum dots; Resonant tunneling; Self-assembled quantum dots; Schottky depletion; Buried metal gate; Electron transport; Magnetic-field dependence; Energy level width; Tunneling transistors; Mode coupling; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Technological sciences; Teknik; Fysicumarkivet A:2001:Gustafson;

    Sammanfattning : In the thesis, three-dimensionally confined resonant tunneling structures were studied experimentally. Two approaches were used for obtaining quantum confinement: gate-defined lateral constriction of double barrier structures, and epitaxial growth of self-assembled quantum dots. LÄS MER

  4. 23. Radiation Oncology Data and Modelling Side Effects after Radiation Therapy

    Författare :Caroline Olsson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; dose and side effect data; dose-volume response; fractionation effect; LQ model; sequential two-phase radiotherapy; head and neck cancer; parotid gland; xerostomia; pelvic radiotherapy; gynecological cancer; pubic bone; pain; data integration; xerostomia;

    Sammanfattning : Although modern radiation therapy techniques have the ability to conform the dose distribution of ionizing radiation tightly around the volume to be treated, unwanted irradiation to surrounding organs remains a problem. The probability of a side effect arising in the normal tissue of a patient after radiation therapy can be modelled by sigmoid mathematical functions known as normal tissue complication probability (NTCP) models. LÄS MER

  5. 24. Automorphic forms and string theory: Small automorphic representations and non-perturbative effects

    Författare :Henrik Gustafsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; instantons; automorphic forms; automorphic representations; Eisenstein series; U-duality; non-perturbative effects; string theory;

    Sammanfattning : This compilation thesis stems from a project with the purpose of determining non-perturbative contributions to scattering amplitudes in string theory carrying important information about instantons, black hole quantum states and M-theory. The scattering amplitudes are functions on the moduli space invariant under the discrete U-duality group and this invariance is one of the defining properties of an automorphic form. LÄS MER

  7. 25. Explorations of University Physics in Abstract Contexts : From de Sitter Space to Learning Space

    Författare :Daniel Domert; Cedric Linder; Ulf Danielsson; Duncan Fraser; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; phenomenography; cosmology; de Sitter space; quantum mechanics; conceptual understanding; epistemology; physics equations; Fysik; Physics; Fysik; Physics with specialization in Physics Education; Fysik med inriktning mot fysikens didaktik;

    Sammanfattning : This is a thesis which contributes to research in two different fields: theoretical physics and physics education research. The common link between these two research areas is that both involve explorations of abstract physics and mathematical representations, but from different perspectives. LÄS MER