Search for dissertations about: "string theory"

Showing result 6 - 10 of 100 swedish dissertations containing the words string theory.

  2. 6. Vacua in String Theory : de Sitter Space and Stability in Flux Compactifications

    Author : Sergio C. Vargas; Ulf Danielsson; Alessandro Tomasiello; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; String theory; Cosmology; Flux Compactifications; Landscape; Swampland;

    Abstract : Our understanding of cosmology has evolved radically in the last decades. Current models demand the presence of dark energy in our universe and the most favored candidate behind this component is a small positive cosmological constant that characterizes a de Sitter (dS) spacetime. READ MORE

  4. 7. 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

  5. 8. 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. 9. 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. 10. Aspects of Yang-Mills Theory : Solitons, Dualities and Spin Chains

    Author : Lisa Freyhult; Antti Niemi; Poul Damgaard; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Theoretical physics; Theoretical Physics; Field theory; String theory; Yang-Mills; Effective models; Supersymmetry; Solitons; Fermion number; Duality; AdS CFT correspondence; Bethe ansatz; Teoretisk fysik; Physics; Fysik;

    Abstract : One of the still big problems in the Standard Model of particle physics is the problem of confinement. Quarks or other coloured particles have never been observed in isolation. Quarks are only observed in colour neutral bound states. The strong interactions are described using a Yang-Mills theory. READ MORE