Back Reaction and Graceful Exit in String Inflationary Cosmology
Abstract
Classical string cosmology consists of two branches related to each other by scalefactor duality: a superinflation branch and a FriedmannRobertsonWalker (FRW) branch. Curvature and string coupling singularity separates the two branches, hence posing ``graceful exit problem'' to superinflationary string cosmology. In an exactly soluble twodimensional compactification model it is shown that quantum back reaction retards curvature and string coupling growth and connects the superinflation branch to the FRW branch without encountering a singularity. This may offer an attractive solution to the graceful exit problem in string inflationary cosmology.
 Publication:

Physical Review Letters
 Pub Date:
 September 1996
 DOI:
 10.1103/PhysRevLett.77.1929
 arXiv:
 arXiv:hepth/9605176
 Bibcode:
 1996PhRvL..77.1929R
 Keywords:

 High Energy Physics  Theory;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology
 EPrint:
 12 pages, ReVTeX