Gravity on a brane in infinite-volume extra space - art. no. 065007

We generalize the mechanism proposed in a previous paper and show that a fo ur-dimensional relativistic tensor theory of gravitation can be obtained on a delta-function brane in flat infinite-volume extra space. In particular, we demonstrate that the induced Ricci scalar gives rise to Einstein's grav ity on a delta-function type brane if the number of space-time dimensions i s bigger than five. The bulk space exhibits the phenomenon of infrared tran sparency. That is to say, the bulk can be probed by gravitons with vanishin g four-dimensional momentum square, while it is unaccessible to higher mode s. This provides an attractive framework for solving the cosmological const ant problem.