This manusript based thesis explores the consequences of string gas cosmology for the moduli problem in string theory. We compile three published papers which set up the formalism and technique of massless string gas cosmology as developed by the author in collaboration with Robert Brandenberger, and explores the consequences of such a framework for late time cosmology. We find that when consistently coupled to the massless background of string theory (given a fixed dilaton), a fluid of massless strings can stabilize all radial and shape moduli of a toroidal compactification of bosonic or heterotic string theory. This stabilization mechanism is consistent with observational bounds coming from fifth force experiments and reproduces all of the desirable features of late time cosmology. We identify the open issues associated with the string gas framework as it stands, and propose directions for future work. We also investigate the possibility that string gas cosmology might offer a dynamical solution to the moduli problem. / Cette these basee par manusript explore les consequences de la cosmologie de gaz des cordes pour le probleme de modules dans la theorie des cordes. Nous compilons trois papiers publies qui installent le formalisme et la technique de la cosmologie de gaz des cordes sans masse comme developpee par l'auteur en collaboration avec Robert Brandenberger, et explorons les consequences d'un tel cadre pour la cosmologie de temps tardives. Nous constatons qu'une fois uniformement couple au fond sans masse de la theorie de corde (donne un dilaton fixe), un fluide des cordes sans masse peut stabiliser tous les modules de radial et de forme d'un compactification toroidal de theorie bosonic ou heterotique de corde. Ce mecanisme de stabilisation est conforme aux limites d'observation venant des experiences de force cinquiemes et reproduit tous les dispositifs souhaitables de cosmologie de temps tardives. Nous identifions les issues ouvertes liees au cadre de gaz de corde sans modification, et proposons des directions pour les travaux futurs. Nous etudions egalement la possibilite que la cosmologie de gaz de corde pourrait offrir une solution dynamique au probleme de modules.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.18778 |
| Date | January 2008 |
| Creators | Patil, Subodh |
| Contributors | Robert Brandenberger (Internal/Supervisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Physics) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | Electronically-submitted theses. |
Page generated in 0.0014 seconds