The vanishing cosmological constant in the four dimensional space-time is
obtained in a 5D Randall-Sundrum model with a brane (B1) located at y=0. The
matter fields can be located at the brane. For settling any vacuum energy
generated at the brane to zero, we need a three index antisymmetric tensor
field AMNP with a specific form for the Lagrangian. For the self-tuning
mechanism, the bulk cosmological constant should be negative.Comment: LaTeX file of 4 pages, to appear in Phys. Rev. Let