BRST quantization of the pure spinor superstring

Understand

We present a derivation of the scattering amplitude prescription for the pure spinor superstring from first principles, both in the minimal and non-minimal formulations, and show that they are equivalent.

• This is achieved by first coupling the worldsheet action to topological gravity and then proceeding to BRST quantize this system.
• Our analysis includes the introduction of constant ghosts and associated auxiliary fields needed to gauge fix symmetries associated with zero modes.
• All fields introduced in the process of quantization can be integrated out explicitly, resulting in the prescriptions for computing scattering amplitudes that have appeared previously in the literature.