Creation of a brane world with Gauss-Bonnet term
  We study a creation of a brane world using an instanton solution. We analyze a brane model with a Gauss-Bonnet term in a bulk spacetime. The curvature of 3-brane is assumed to be closed, flat, or open. We construct instanton solutions with branes for those models, and calculate the value of the actions to discuss an initial state of a brane universe. 
Koh-suke Aoyanagi and Kei-ichi Maeda