Condensates and Singularities in String Theory

Abstract

We derive a class of solutions to the string sigma-model equations for the closed bosonic string. The tachyon field is taken to form a constant condensate and the beta-function equations at one-loop level are solved for the evolution of the metric and the dilaton. The solutions represent critical string theories in arbitrary dimensions. The spectrum of the subclass of models with a linearly rising asymptotic dilaton is found using the Feigin-Fuks method. Certain approximate solutions arising in string field theory are used to illustrate the results explicitly. An argument based on conformal invariance leads to the conjecture that that stringy corrections to at least some singular spacetimes in general relativity result in non-singular metrics. We use the singularities of the big-bang/crunch type appearing in our models to examine this conjecture.

20 pages, DAMTP-R92-40, IUHET 242

References in corpus (3)

• A Closed, Expanding Universe in String Theory
• Strings on Curved Spacetimes: Black Holes, Torsion, and Duality
• Heterotic String Models in Curved Spacetime

Cited by in corpus (8)

• Type 0 Brane Inflation from Mirage Cosmology
• Rolling Closed String Tachyons and the Big Crunch
• Off-shell Closed String Amplitudes: Towards a Computation of the Tachyon Potential
• Back Reaction of Strings in Self-Consistent String Cosmology
• Effective Tachyonic Potential in Closed String Field Theory
• Cosmological Evolution of a Brane Universe in a Type 0 String Background
• Comments on Tachyon Potentials in Closed and Open-Closed String Theories
• A tachyonic extension of the stringy no-go theorem