String theory provides landmarks fixing RS branes' positions:   Possibility to deduce large mass hierarchy from small numbers
  Two-branes RS-I 5-dimensional model is generalized in higher dimensional string-induced theory with dilaton and $n$-form field. It is supposed that "hidden" and "visible" Randall-Sundrum branes are located at the boundaries of region of space-time where low-energy supergravity description is valid. This permits to determine mass scale hierarchy which calculated value proves to be strongly dependent on dimensionalities of subspaces. 
Boris L. Altshuler (P.N. Lebedev Physical Institute)