Electromagnetic contributions to lepton g-2 in a thick brane-world

We consider Standard Model fields living inside a thick four-dimensional fl at brane embedded in a (possibly warped) five-dimensional space-time and es timate the electromagnetic corrections to the anomalous magnetic moment (g - 2) of the electron and muon by including virtual massive fermion and gaug e boson states. Constraints on the mass of the "excited" states (or thickne ss of the brane-world) are obtained. (C) 2000 Elsevier Science B.V. All rig hts reserved.