2005/11/13 by Gregory Gabadadze, Yanwen Shang · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #hep-th
paper · pdf · doi:10.1016/j.physletb.2006.03.002
published as Phys.Lett.B635:235-242,2006 · 17 pages; 6 figures
arxiv created 2005/11/13 · openalex publication_date 2006/03/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
In [G. Gabadadze, Y. Shang, hep-th/0506040] we discussed a classically constrained model of gravity. This theory contains known solutions of General Relativity (GR), and admits solutions that are absent in GR. Here we study cosmological implications of some of these new solutions. We show that a spatially-flat de Sitter universe can be created from “nothing”. This universe has boundaries, and its total energy equals to zero. Although the probability to create such a universe is exponentially suppressed, it favors initial conditions suitable for inflation. Then we discuss a finite-energy solution with a nonzero cosmological constant and zero space–time curvature. There is no tunneling suppression to fluctuate into this state. We show that for a positive cosmological constant this state is unstable—it can rapidly transition to a de Sitter universe providing a new unsuppressed channel for inflation. For a negative cosmological constant the space–time flat solutions is stable.