A quasi-thick codimension 2 braneworld

We study a codimension 2 braneworld in the Einstein-Gauss-Bonnet gravity. We carefully examine the structure of possible singularities in the system which characterize the braneworld through matching conditions. We find that the thickness of the brane can be incorporated as a distributional source, which we dub quasi-thickness. On the basis of our formalism, we analyse the linearized gravity and show that the conventional Einstein gravity can be recovered on the brane. In the nonlinear regime, however, we find corrections due to the thickness and the bulk geometry. We also point out the possibility that the thickness plays the role of dark energy/dark matter in the universe.