Nonperturbative Tests of the Parent/Orbifold Correspondence in   Supersymmetric Gauge Theories
  It has been shown that a procedure analogous to orbifolding in string theory, when applied to certain large N field theories, leaves correlators invariant perturbatively. We test nonperturbative agreement of some aspects of the orbifolded and non-orbifolded theories. More specifically, we find that the period matrices of parent and orbifolded Seiberg-Witten theories are related, even away from the 't Hooft limit. We also check that any large N theory which has an infrared conformal fixed point and satisfies certain anomaly positivity constraints required by theories with fixed points will continue to satisfy those constraints after orbifolding. We discuss extensions of these results to finite N. 
J. Erlich and A. Naqvi (M.I.T)