Twistors, strings and supersymmetric gauge theories

Understand

This thesis is concerned with the study of scattering amplitudes in four-dimensional conformal field theories, more particularly the N=4 super-Yang-Mills theory.

• We study this theory first at tree level by using twistor space techniques and review the twistor string models that were proposed to describe it.
• Then, we turn to the issue of iteration relations and all loop ansatze for scattering amplitudes.
• We review the unitarity method for computing scattering amplitudes and discuss the Wilson loop--scattering amplitude duality that was inspired by the strong-coupling prescription of Alday and Maldacena for scattering amplitudes.