Integrated vertices

Definition 5: Integrated vertices are deformations of the string
worldsheet theory, preserving the existence of the BRST structure:

— this is the integrated vertex.

As we already said, there is the correspondence between physical states of the worldsheet theory and its deformations. This means that for every unintegrated vertex there exists a corresponding integrated vertex. The correspondence is described by the descent procedure, which goes as follows. Given some unintegrated vertex , do the following:

Theorem 6: Exist operators and defined in (4) and (5) exist.

The main result in this talk is the proof of this theorem for the superstring in .