String gas cosmology

  title={String gas cosmology},
  author={T. Battefeld and S. Watson},
  journal={Reviews of Modern Physics},
A critical review and summary of string gas cosmology is presented. A pedagogical derivation of the effective action starting from string theory, emphasizing the necessary approximations that must be invoked, is included. Working in the effective theory, that at late times it is not possible to stabilize the extra dimensions by a gas of massive string winding modes is demonstrated. Additional string gases are considered that contain so-called enhanced symmetry states. These string gases are… Expand

Figures from this paper

Enhanced symmetries, duality invariance and moduli stabilization in string gas cosmology
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 ofExpand
Aspects of String Cosmology
We review recent progress in string cosmology, where string dualities are applied so as to obtain complete cosmological evolutions, free of any essential singularities. Two classes of models areExpand
More on the spectrum of perturbations in string gas cosmology
String gas cosmology is rewritten in the Einstein frame. In an effective theory in which a gas of closed strings is coupled to a dilaton gravity background without any potential for the dilaton, theExpand
String Theory and Pre-big bang Cosmology
Summary. In string theory, the traditional picture of a Universe that emerges from the inflation of a very small and highly curved space-time patch is a possibility, not a necessity: quite differentExpand
Thermodynamics of string gas
In these lecture notes I give a pedagogical introduction to the thermodynamics of ideal string gases. The computation of thermodynamic quantities in the canonical ensemble formalism will be shown inExpand
u 2 0 1 2 ) 0 8 3 Aspects of String Cosmology
We review recent progress in string cosmology, where string dualities are applied so as to obtain complete cosmological evolutions, free of any essential si ngularities. Two classes of models areExpand
The effect of α′ corrections in string gas cosmology
In the Brandenberger–Vafa scenario of string gas cosmology, the Universe starts as a small torus of string length dimension filled with a hot gas of strings. In such extreme conditions, in additionExpand
Massless D-strings and moduli stabilization in type I cosmology
We consider the cosmological evolution induced by the free energy F of a gas of maximally supersymmetric heterotic strings at finite temperature and weak coupling in dimension D ≥ 4. We show that F,Expand
String gas cosmology: progress and problems
String gas cosmology is a model of the evolution of the very early universe based on fundamental principles and key new degrees of freedom of string theory which are different from those of pointExpand
Quantum cosmology at finite temperature in superstring theory
We study cosmology induced by an ideal superstring gas at finite temperature. The thermal/quantum effects of the string gas generate a nontrivial effective potential at one-loop level. At certainExpand


Aspects of string-gas cosmology at finite temperature
We study string-gas cosmology in dilaton gravity, inspired by the fact that it naturally arises in a string theory context. Our main interest is the thermodynamical treatment of the string-gas andExpand
The cosmology of massless string modes
We consider the spacetime dynamics of a gas of closed strings in the context of general relativity in a background of arbitrary spatial dimensions. Our motivation is primarily late time string gasExpand
Interaction rates in string gas cosmology
We study string interaction rates in the Brandenberger-Vafa scenario, the very early universe cosmology of a gas of strings. This cosmology starts with the assumption that all spatial dimensions areExpand
Loitering phase in brane gas cosmology
Abstract Brane gas cosmology (BGC) is an approach to M-theory cosmology in which the initial state of the Universe is taken to be small, dense and hot, with all fundamental degrees of freedom nearExpand
Radion stabilization by stringy effects in general relativity
We consider the effects of a gas of closed strings (treated quantum mechanically) on a background where one dimension is compactified on a circle. After we address the effects of a time-dependentExpand
Late-time dynamics of brane gas cosmology
Brane gas cosmology is a scenario inspired by string theory which proposes a simple resolution to the initial singularity problem and gives a dynamical explanation for the number of spatialExpand
Numerical experiments on string cosmology
Abstract We investigate some classical aspects of fundamental strings via numerical experiments. In particular, we study the thermodynamics of a string network within a toroidal universe, as aExpand
Brane gas cosmology in M theory: Late time behavior
We investigate the late-time behavior of a universe containing a supergravity gas and wrapped 2-branes in the context of M theory compactified on ${T}^{10}.$ The supergravity gas tends to driveExpand
Brane gases in the early Universe
Over the past decade it has become clear that fundamental strings are not the only fundamental degrees of freedom in string theory. D-branes are also part of the spectrum of fundamental states. InExpand
Elements of string cosmology
Abstract Aspects of string cosmology for critical and non-critical strings are discussed emphasizing the necessity to account for the dilaton dynamics for a proper incorporation of “large-small”Expand