Search for dissertations about: "string"

Showing result 1 - 5 of 187 swedish dissertations containing the word string.

2. 1. Holographic Wilson Loops : Quantum String Corrections

   Author : Daniel Ricardo Medina Rincon; Konstantin Zarembo; Gianluca Grignani​; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Gauge-string correspondence; AdS CFT; Wilson loops; String theory; Theoretical Physics; Teoretisk fysik;

   Abstract : The gauge-string duality has been one of the most exciting areas in theoretical physics as it connects strongly coupled field theories with weakly interacting strings. The present thesis concerns the study of Wilson loops in this correspondence. READ MORE

4. 2. Torn, Spun and Chopped : Various Limits of String Theory

   Author : Fredric Kristiansson; Ulf Danielsson; Per Sundell; Bo Sundborg; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Theoretical physics; Theoretical physics; String theory; D-branes; Non-commutative open string theory; AdS CFT; Higher spin gauge theory; BMN; String bits; Fermion doubling; Teoretisk fysik; Physics; Fysik;

   Abstract : For the first time in the history of physics we stand in front of a theory that might actually serve as a unification of it all - string theory. It provides a self-consistent framework for gravity and quantum mechanics, which naturally incorporates matter and gauge interactions of the type seen in the standard model. READ MORE

5. 3. On string integrability : A journey through the two-dimensional hidden symmetries in the AdS/CFT dualities

   Author : Valentina Giangreco Marotta Puletti; Konstantin Zarembo; Gleb Arutyunov; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; String Theory; AdS-CFT correspondence; Integrable Field theory; Sigma models; S-matrix; Factorized Scattering; Physics; Fysik; Mathematical physics; Matematisk fysik; Theoretical Physics; teoretisk fysik;

   Abstract : One of the main topics in the modern String Theory are the conjectured string/gauge (AdS/CFT) dualities. Proving such conjectures is extremely difficult since the gauge and string theory perturbative regimes do not overlap. In this perspective, the discovery of infinitely many conserved charges, i.e. READ MORE

6. 4. Automorphic string amplitudes

   Author : Henrik Gustafsson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Eisenstein series; string theory; automorphic forms; U-duality; non-perturbative effects; Whittaker vectors; instantons;

   Abstract : This thesis explores the non-perturbative properties of higher derivative interactions appearing in the low-energy expansion of four-graviton scattering amplitudes in toroidal compactifications of type IIB string theory. We summarise the arguments for finding such higher derivative corrections in terms of automorphic forms using U-duality, supersymmetry and string perturbation theory. READ MORE

7. 5. The bowed string

   Author : Knut Guettler; KTH; []
   Keywords : Bowed string; violin; musical acoustics; musical transient; anomalous low frequencies; Helmholtz motion;

   Abstract : Of the many waveforms the bowed string can assume, theso-called "Helmholtz motion" (Helmholtz 1862) gives the fullestsound in terms of power and overtone richness. The developmentof this steady-state oscillation pattern can take manydifferent paths, most of which would include noise caused bystick-slip irregularities of the bow-string contact. READ MORE