Moduli space metric for maximally-charged dilaton black holes
  The system consisting of slowly-moving, maximally charged, nonrotating dilaton black holes is investigated. We obtain the metric on the moduli space of the system in the low-velocity limit. We find that: (1) only two-body interactions exist between the extreme black holes in string theory; (2) the mutual interaction between the black holes vanishes if the dilaton can be interpreted as a Kaluza-Klein scalar; and (3) for general dilaton couplings, there exist many-body interactions among the extreme black holes. We analyze the low-energy classical scattering of the two extreme black holes in string theory by utilizing the moduli space metric. 
Kiyoshi Shiraishi
gr-qc