In the Randall–Sundrum (RS) brane-world model a singular delta-function source is matched by the second derivative of the warp factor. So one should take possible curvature corrections in the effective action of the RS models in the Gauss–Bonnet (GB) form. We present a linearized treatment of gravity in the RS brane-world with the Gauss–Bonnet modifications to Einstein gravity. We give explicit expressions for the Neumann propagator in arbitrary D dimensions and show that a bulk GB term gives, along with a tower of Kaluza–Klein modes in the bulk, a massless graviton on the brane, as in the standard RS model. Moreover, a nontrivial GB coupling can allow a new branch of solutions with finite Planck scale and no naked bulk singularity, which might be useful to avoid some of the previously known "no-go theorems" for RS brane-world compactifications.
Warm inflation in the DGP brane-world model
