N=4 SYM on R times S^3 and PP-Wave
  We consider the radial quantization of N=4 super Yang-Mills (SYM) in 4 dimensions, i.e., N=4 SYM on a cylinder R times S^3. We construct the generators of superconformal symmetry in the case of U(N) gauge group, generalizing the earlier work by Nicolai et al. for U(1) gauge group. We study how these generators contract to the symmetry of pp-wave when they act on a state with large R-charge. 
Kazumi Okuyama