Dynamics of supertubes

We find the evolution of arbitrary excitations on 2-charge supertubes, by mapping the supertube to a string carrying traveling waves. We argue that when the coupling is increased from zero the energy of excitation leaks off to infinity, and when the coupling is increased still further a new set of long lived excitations emerge. We relate the excitations at small and large couplings to excitations in two different phases in the dual CFT. We conjecture a way to distinguish bound states from unbound states among 3-charge BPS geometries; this would identify black hole microstates among the complete set of BPS geometries.