Gravity waves from inflating brane or Mirrors moving in adS5

We study tensor perturbations in a model with inflating Randall-Sundrum-type brane embedded in five-dimensional anti-de Sitter (AdS5) bulk. In this model, a natural in-vacuum of gravitons is the vacuum defined in static AdS5 frame. We show that this vacuum is, in fact, the same as the in-vacuum defined in the frame with de Sitter (dS4) slicing, in which the brane is at rest. Thus, during inflation, gravitons on and off the brane remain in their …