String gas cosmology

  title={String gas cosmology},
  author={Thorsten J. Battefeld and Scott 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… 

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 of

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 are

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, the

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 different

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 in

Primordial Fluctuations in String Cosmology

This thesis is dedicated to the study of inflationary scenarios based on string theory. Inflation is a brief period of accelerated expansion in the very early Universe which gives natural

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 are

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,

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 certain

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 point



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 and

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 gas

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 are

Loitering phase in brane gas cosmology

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-dependent

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 spatial

Numerical experiments on string cosmology

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 drive

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. In

Elements of string cosmology