Brane collisions and braneworld cosmology
  Recently, we proposed a new braneworld model [GIT] in which the collision of a brane universe and a vacuum bubble coming from the extra-dimension is utilized as a trigger of brane big-bang. In this article, mainly reviewing this model, we briefly summarize cosmological braneworld scenarios in which collision of branes plays an important role. 
Uchida Gen, Akihiro Ishibashi, and Takahiro Tanaka