Superconductor-insulator transition of the Josephson-junction array model in the spherical limit

We have studied the superconductor-insulator transition of the Josephson-ju nction array model in the spherical limit. Through a finite-size scaling an alysis of various quantities, such as the superfluid stiffness, the compres sibility, and the energy gap, in very large systems, we have found that the dynamical critical exponent is z = 1.0 and the correlation length critical exponent is nu = 1.0. The estimated value of the universal resistance at t he transition is consistent with the exact analytic result.