Non-Perturbative Contributions in the Plane-Wave/BMN Limit
  This talk surveys recent work on the contribution of instantons to the anomalous dimensions of BMN operators in $\calN=4$ supersymmetric Yang--Mills theory and the corresponding non-perturbative contributions to the mass-matrix of excited string states in maximally supersymmetric plane-wave string theory. The dependence on the coupling constants and the impurity mode numbers in the gauge theory and string theory are in striking agreement.   [Presented by MBG at the Einstein Symposium, Bibliotecha Alexandrina, June 4--6 2005.] 
Michael B. Green, Stefano Kovacs, Aninda Sinha