Super-Poincare covariant quantization of the superstring

Using pure spinors, the superstring is covariantly quantized. For the first time, massless vertex operators are constructed and scattering amplitudes are computed in a manifestly ten-dimensional super-Poincare covariant manne r. Quantizable non-linear sigma model actions are constructed for the super string in curved backgrounds, including the AdS(5) x S-5 background with Ra mond-Ramond flux.