Search for dissertations about: "symmetry theory"

Showing result 1 - 5 of 189 swedish dissertations containing the words symmetry theory.

2. 1. Dualities, Symmetries and Unbroken Phases in String Theory : Probing the Composite Nature of the String

   Author : Johan Engquist; Joseph Minahan; Charlotte Kristjansen; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Theoretical Physics; String Theory; M-Theory; Higher Spin Gauge Theory; Super Yang-Mills Theory; Anti-de Sitter Spacetime; Singletons; Massless Higher Spin Gauge Fields; AdS CFT Correspondence; Spin Chains; Semiclassical Strings; Tensionless Limits; Conformal Symmetry; Supersymmetry; Higher Spin Gauge Symmetry; Integrability; Fysik; Physics; Fysik;

   Abstract : The thesis treats aspects of string/M-theory in anti-de Sitter spacetimes and their supersymmetric completions. By applying the AdS/CFT correspondence, as well as models of spin chains and singletons, we try to attain a better understanding of the underlying symmetries and the unbroken phases of string/M-theory. READ MORE

4. 2. The Quest for M-theory

   Author : Ulf Gran; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; supersymmetry; solitons; gauge symmetry; M-theory; string theory; duality; p-branes; D-branes; superspace; supergravity;

   Abstract : In ten dimensions, there exist five consistent string theories and in eleven dimensions there is a unique supergravity theory. When trying to find the fundamental theory of nature this is clearly an "embarrassment of riches". In the mid 90s, however, it was discovered that these theories are all related via a kind of transformation called duality. READ MORE

5. 3. Symmetry in Randomness : Additive Functionals and Symmetries of Random Trees and Tree-Like Graphs

   Author : Christoffer Olsson; Stephan Wagner; Ralph Neininger; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Random trees; Random graphs; Additive functionals; Automorphisms; Mathematics; Matematik;

   Abstract : Properties of symmetries in random trees and tree-like graphs are explored. The primary structures studied are Galton-Watson trees, unlabeled unordered trees as well as labeled subcritical graphs. READ MORE

6. 4. Crystallization of the superconducting phase in unconventional superconductors

   Author : Patric Holmvall; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; pattern formation; spontaneous symmetry breaking; Andreev bound states; mesoscopic superconductivity; phase crystals; thin superconducting films; phase transitions; non-local Ginzburg-Landau theory; time-reversal symmetry; flat bands; unconventional superconductivity; quasiclassical theory; translational symmetry; cuprates; inhomogeneous superconductivity;

   Abstract : Superconductivity is a macroscopic quantum phenomenon, in the sense that a macroscopic number of electrons form a pair condensate, that occupies a single ground state. The electrons in this state are phase-coherent, breaking global U (1)-symmetry, and spatial variations of the phase imply superflows that usually cost kinetic energy, resulting in a uniform and rigid phase. READ MORE

7. 5. Algorithmic Methods in Combinatorial Algebra

   Author : Anna Torstensson; Algebra; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; algebraic geometry; field theory; Number Theory; maximal symmetry group; resultant; SAGBI basis; Orthogonal decomposition; algebra; group theory; Talteori; fältteori; algebraisk geometri; gruppteori;

   Abstract : This thesis consists of a collection of articles all using and/or developing algorithmic methods for the investigation of different algebraic structures. Part A concerns orthogonal decompositions of simple Lie algebras. The main result of this part is that the symplectic Lie algebra C3 has no orthogonal decomposition of so called monomial type. READ MORE