Effective gravity andOSp(N,4)-invariant matter

We reexamine the $\mathrm{OSp}\mathrm{}(N,4\mathrm{})\mathrm{}$-invariant interacting model of massless chiral and gauge superfields, whose superconformal invariance was instrumental both in proving the all-order no-renormalization of the mass and chiral self-interaction Lagrangians and in determining the linear superfield renormalization needed. We show that the renormalization of the gravitational action modifies only the cosmological term, without affecting higher-order tensors. This could explain why the effect of the cosmological constant is shadowed by the effects of Newtonian gravity.