From Multiloop Spinor Helicity Technique to String Reorganization †

Multiloop stringlike formulas for QED.

Multiloop gauge-theory amplitudes written in the Feynman-parameter representation are poised to take advantage of two important developments of the last decade: the spinor-helicity technique and the superstring reorganization. The former has been considered in a previous article; the latter will be elaborated in this paper. We show here how to write multiloop string-like formulas in the Feynman...

Multiloop Superstring Amplitudes from Non-minimal Pure Spinor Formalism

Using the non-minimal version of the pure spinor formalism, manifestly super-Poincaré covariant superstring scattering amplitudes can be computed as in topological string theory without the need of picture-changing operators. The only subtlety comes from regularizing the functional integral over the pure spinor ghosts. In this paper, it is shown how to regularize this functional integral in a B...

Multiloop calculations in the string-inspired formalism: The single spinor loop in QED.

Topological String

Following suggestions of Nekrasov and Siegel, a non-minimal set of fields are added to the pure spinor formalism for the superstring. Twistedˆc = 3 N=2 generators are then constructed where the pure spinor BRST operator is the fermionic spin-one generator, and the formalism is interpreted as a critical topological string. Three applications of this topological string theory include the super-Po...

Covariant Multiloop Superstring Amplitudes

Talk given at Strings 2004 In these proceedings, the multiloop amplitude prescription using the super-Poincaré invariant pure spinor formalism for the superstring is reviewed. Unlike the RNS prescription , there is no sum over spin structures and surface terms coming from the boundary of moduli space can be ignored. Massless N-point multiloop amplitudes vanish for N < 4, which implies (with two...