Detecting extra dimensions with gravity wave spectroscopy: the black   string brane-world
  Using the black string between two branes as a model of a brane-world black hole, we compute the gravity wave perturbations and identify the features arising from the additional polarizations of the graviton. The standard four-dimensional gravitational wave signal acquires late-time oscillations due to massive modes of the graviton. The Fourier transform of these oscillations shows a series of spikes associated with the masses of the Kaluza-Klein modes, providing in principle a spectroscopic signature of extra dimensions. 
Sanjeev S. Seahra, Chris Clarkson, Roy Maartens (Portsmouth)