Gregory-Laflamme encounters Superradiance

A bstract We investigate the effect of superradiant scattering gravitational perturbations on stability rotating black strings, focusing six dimensional equal-spinning Myers-Perry string. find that rapidly strings are unstable to modes within a bounded range string lengths. The instability occurs because momentum along direction creates potential barrier allows for confinement modes. Yet, five holes do not have stable particle orbits so, unlike other known systems, these remain with sufficiently high azimuthal mode number — this is ‘finite- m ’ instability. For some parameters, competes Gregory-Laflamme instability, but otherwise exists independently. onset degenerate and branches multiple steady-state solutions. This paper first trilogy: in next two, we construct two distinct families emerging from (the ‘black resonator strings’ ‘helical strings’). argue similar physics present 5-dimensional Kerr D > 6 strings.