  If our Universe is a 3+1 brane in a warped 4+1 dimensional bulk so that its
expansion can be understood as the motion of the brane in the bulk, the time
dependence of the boundary conditions for arbitrary bulk fields can lead to
particle creation via the dynamical Casimir effect. In this talk I report
results for the simplest such scenario, when the only particle in the bulk is
the graviton and the bulk is the 5 dimensional anti-de Sitter spacetime.
