Search for dissertations about: "Quantum field theory low energy"

Showing result 1 - 5 of 33 swedish dissertations containing the words Quantum field theory low energy.

  2. 1. One-dimensional theory of the quantum Hall system

    Author : Emil Johansson Bergholtz; Anders Karlhede; Nicholas Read; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; fractional quantum Hall effect; thin torus; spin chains; conformal field theory; strong correlations; non-abelian states; Condensed matter physics; Kondenserade materiens fysik; Theoretical Physics; teoretisk fysik;

    Abstract : The quantum Hall (QH) system---cold electrons in two dimensions in a perpendicular magnetic field---is a striking example of a system where unexpected phenomena emerge at low energies. The low-energy physics of this system is effectively one-dimensional due to the magnetic field. READ MORE

  4. 2. Meson Properties in Partially Quenched Effective Field Theory

    Author : Niclas Danielsson; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; statistical physics; gravitation; relativity; quantum mechanics; classical mechanics; Mathematical and general theoretical physics; Fysik; Chiral Perturbation Theory; masses; decay constants; Physics; electromagnetic interactions; Strong interactions; pseudoscalar mesons; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik;

    Abstract : Mass corrections and decay constants for light mesons have been calculated in Partially Quenched Chiral Perturbation Theory. The calculations of the charged meson masses have been performed to third order, first for degenerate quark masses, and then, in a second project, for the general case. READ MORE

  5. 3. Field Theories and Vortices with Nontrivial Geometry

    Author : Kristel Torokoff; Antti Niemi; Masud Chaichian; Uppsala universitet; []
    Keywords : Theoretical physics; theoretical physics; gauge field theory; knot theory; spontaneously broken symmetry; effective model; numerical calculation; soliton; vortex; electromagnetic plasma; Teoretisk fysik;

    Abstract : This thesis investigates aspects of field theories and soliton solutions with nontrivial topology. In particular we explore the following effective models: a limited sector of the scalar Electroweak theory called extended Abelian Higgs model, and a classical mechanics model derived from the low energy SU(2) Yang-Mills theory. READ MORE

  6. 4. Many-Body effects in Semiconductor Nanostructures

    Author : Carl-Johan Wesslén; Eva Lindroth; Morten Førre; Stockholms universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; coupled cluster; nanostructure; quantum dot; quantum ring; concentric quantum ring; many body pertubation theory; fysik; Physics;

    Abstract : Low dimensional semiconductor structures are modeled using techniques from the field of many-body atomic physics. B-splines are used to create a one-particle basis, used to solve the more complex many-body problems. READ MORE

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

    Author : Sergey Slizovskiy; Antti Niemi; Andrey Losev; Andrey Marshakov; Uppsala universitet; []
    Keywords : 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;

    Abstract : 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. READ MORE