Sökning: "Supergravity"
Visar resultat 16 - 20 av 30 avhandlingar innehållade ordet Supergravity.
16. Vacua in String Theory : de Sitter Space and Stability in Flux Compactifications
Sammanfattning : 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. LÄS MER
17. Arithmetic and Hyperbolic Structures in String Theory
Sammanfattning : This thesis consists of an introductory text followed by two separate parts which may be read independently of each other. In Part I we analyze certain hyperbolic structures arising when studying gravity in the vicinity of spacelike singularities (the BKL-limit). LÄS MER
18. Aspects of vacuum moduli in string theory
Sammanfattning : In this thesis we explore geometric aspects of the space of vacua in supersymmetric string compactifications. More specifically, we will look at heterotic strings compactified on Calabi-Yau manifolds and, separately, G2 structure manifolds. LÄS MER
19. Degenerate Geometries, Supersymmetry and Duality
Sammanfattning : String theory is a theory attempting to unify gravity with the electro-weak and strong interactions so successfully described by Quantum Field Theory. The implications of String Theory is not fully understood since it is still not a complete theory. LÄS MER
20. Smooth particles and exotic strings
Sammanfattning : During the last few decades quantum gauge field theories in general, and the Electroweak Standard Model in particular, have been very successful in the description of the fundamental constituents of matter and their interactions. However, such models all meet with severe shortcomings, e.g. LÄS MER