Asymptotics of solutions of the wave equation on de Sitter-Schwarzschild   space
  Solutions to the wave equation on de Sitter-Schwarzschild space with smooth initial data on a Cauchy surface are shown to decay exponentially to a constant at temporal infinity, with corresponding uniform decay on the appropriately compactified space. 
Richard Melrose, Ant\^onio S\'a Barreto, Andr\'as Vasy