Assisted inflation in the Randall–Sundrum scenario

We extend the Randall–Sundrum (RS) model by adding a fundamental scalar field in the bulk, then study the multi-field assisted inflationary solution on the brane. It is shown that this model not only satisfies observations, but also provides a solution to the hierarchy problem. Furthermore in comparison to the chaotic inflation model with a single field in four space–time dimensions, the parameters in our model required for a successful inflation are natural.