Scalar and electromagnetic fields of static sources in higher   dimensional Majumdar-Papapetrou spacetimes
  We study scalar massless and electromagnetic fields from static sources in a static higher dimensional spacetime. Exact expressions for static Green's functions for such problems are obtained in the background of the Majumdar-Papapetrou solutions of the Einstein-Maxwell equations. Using this result we calculated the force between two scalar or electric charges in the presence of one or several extremely charged black holes in equilibrium in the higher dimensional spacetime. 
Valeri Frolov and Andrei Zelnikov
hep-th gr-qc