2005/11/25 by Ruoyu Bao, Marcela Carena, Joseph Lykken +3 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Brane #Brane cosmology #Classical mechanics #Cosmology and Gravitation Theories #Curvature #Discontinuity (linguistics) #Extra dimensions #Gauge theory #Geometry #Gravitation #Graviton #Massive gravity #Mathematical analysis #Mathematical physics #Noncommutative and Quantum Gravity Theories #Observable #Physics #Quantum mechanics #Tachyon #Theoretical physics #Warp drive #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.73.064026
published as Phys.Rev.D73:064026,2006 · 43 pages, 13 figures
arxiv created 2005/11/25 · openalex publication_date 2006/03/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Gravity in five-dimensional braneworld backgrounds often exhibits problematic features, including kinetic ghosts, strong coupling, and the van Dam-Veltman-Zakharov (vDVZ) discontinuity. These problems are an obstacle to producing and analyzing braneworld models with interesting and potentially observable modifications of 4d gravity. We examine these problems in a general AdS5/AdS4 setup with two branes and localized curvature from arbitrary brane kinetic terms. We use the interval approach and an explicit straight gauge-fixing. We compute the complete quadratic gauge-fixed effective 4d action, as well as the leading cubic order corrections. We compute the exact Green's function for gravity as seen on the brane. In the full parameter space, we exhibit the regions which avoid kinetic ghosts and tachyons. We give a general formula for the strong coupling scale, i.e., the energy scale at which the linearized treatment of gravity breaks down, for relevant regions of the parameter space. We show how the vDVZ discontinuity can be naturally but nontrivially avoided by ultralight graviton modes. We present a direct comparison of warping versus localized curvature in terms of their effects on graviton mode couplings. We exhibit the first example of Dvali-Gabadadze-Porrati (DGP)-like crossover behavior in a general warped setup.