Stability analysis of the Randall-Sundrum braneworld in presence of bulk   scalar
  The stability problem of Randall-Sundrum braneworld is readdressed in the light of stabilizing bulk scalar fields. It is shown that in such scenario the instability persists because of back-reaction even when an arbitrary potential is introduced for a canonical scalar field in the bulk. It is further shown that a bulk scalar field can indeed stabilize the braneworld when it has a tachyon-like action. The full back-reacted metric in such model is derived and a proper resolution of the hierarchy problem (for which the Randall Sundrum scenario was originally proposed) is found to exist by suitable adjustments of the parameters of the scalar potential. 
Debaprasad Maity, Soumitra SenGupta, Sourav Sur