Radion Mass is Milli-eV in the Goldberger-Wise Stabilization Mechanism

A complete calculation of the radion mass has been given by Tanaka and Montes, hep-th/0001092, and also by Csaki, Graesser and Kribs (in preparation), which both obtain the TeV-scale. It seems likely that the problem with our computation was neglect of the back-reaction of the scalar field on the graviton zero mode, and consequent contributions to the radion kinetic term from the gravitational part of the Lagrangian. We thank T. Tanaka and C. Csaki for pointing out their results to us.