Syracuse University SURFACE Physics College of Arts and Sciences 2-6-2007 Living on a dS Brane: Effects of KK modes on Inflation Scott Watson Department of Physics, Syracuse University, Syracuse, NY Claudia De Rham Dept. of Physics & Astronomy, McMaster University, Hamilton ON Follow this and additional works at: https://surface.syr.edu/phy Part of the Physics Commons Recommended Citation Watson, Scott and Rham, Claudia De, "Living on a dS Brane: Effects of KK modes on Inflation" (2007). Physics. 411. https://surface.syr.edu/phy/411 This Article is brought to you for free and open access by the College of Arts and Sciences at SURFACE. It has been accepted for inclusion in Physics by an authorized administrator of SURFACE. For more information, please contact
[email protected]. Living on a dS brane: Effects of KK modes on inflation Claudia de Rham1,2, ∗ and Scott Watson3, † 1Dept. of Physics & Astronomy, McMaster University, Hamilton ON, Canada 2Perimeter Institute for Theoretical Physics, Waterloo, ON, Canada 3Physics Department, University of Toronto, Toronto, ON, Canada (Dated: February 2, 2008) We develop a formalism to study non-local higher-dimensional effects in braneworld sce- narios from a four-dimensional effective theory point of view and check it against the well- known Garriga-Tanaka result in the appropriate limit. We then use this formalism to study the spectrum of density perturbations during inflation as seen from the lower-dimensional effective theory. In particular, we find that the gravitational potential is greatly enhanced at short wavelengths. The consequences to the curvature perturbations are nonetheless very weak and will lead to no characteristic signatures on the power spectrum.