1999/05/31 by Damien A. Easson, Robert Brandenberger, Robert H. Brandenberger · 7 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Relativity and Gravitational Theory #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1088/1126-6708/1999/09/003
published as JHEP 9909:003, 1999 · 8 pages, 3 figures, LaTex; minor changes; published in JHEP 9909:003, 1999
openalex publication_date 1999/09/06 · arxiv created 1999/09/19 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider the theory obtained by adding to the usual string frame dilaton gravity action specially constructed higher derivative terms motivated by the limited curvature construction of [MukhanovET1992a] and determine the spatially homogeneous and isotropic solutions to the resulting equations of motion. All solutions of the resulting theory of gravity with these symmetries are nonsingular and all curvature invariants are bounded. For initial conditions inspired by the pre-big-bang scenario solutions exist which correspond to a spatially flat Universe starting in a dilaton-dominated superinflationary phase with H > 0 and having a smooth transition to an expanding Friedmann Universe with H < 0. Hence, the graceful exit problem of pre-big-bang cosmology is solved in a natural way.