Interaction rates in string gas cosmology

Journal Article · Mon Nov 15 04:00:00 EST 2004 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.70.106010· OSTI ID:20698064

Danos, Rebecca; Frey, Andrew R; Mazumdar, Anupam ^[1]

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1. Department of Physics, University of California, Los Angeles, Los Angeles, California 90095 (United States)

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 compact and initially have string scale radii; some dimensions grow due to some thermal or quantum fluctuation which acts as an initial expansion velocity. Based on simple arguments from the low-energy equations of motion and string thermodynamics, we demonstrate that the interaction rates of strings are negligible, so the common assumption of thermal equilibrium cannot apply. We also present a new analysis of the cosmological evolution of strings on compact manifolds of large radius. Then we discuss modifications that should be considered to the usual Brandenberger-Vafa scenario. To confirm our simple arguments, we give a numerical calculation of the annihilation rate of winding strings. In calculating the rate, we also show that the quantum mechanics of strings in small spaces is important.

• OSTI ID: 20698064
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 10 Vol. 70; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANNIHILATION
COSMOLOGY
EQUATIONS OF MOTION
FLUCTUATIONS
QUANTUM FIELD THEORY
QUANTUM MECHANICS
STRING MODELS
THERMAL EQUILIBRIUM
THERMODYNAMICS
UNIVERSE
VELOCITY