The complex null string, Galilean conformal algebra and scattering equations

Understand

The scattering equation formalism for scattering amplitudes, and its stringy incarnation, the ambitwistor string, remains a mysterious construction.

• In this paper, we pursue the study a gauged-unfixed version of the ambitwistor string known as the null string.
• We explore the following three aspects in detail; its complexification, gauge fixing, and amplitudes.
• We first study the complexification of the string; the associated symmetries and moduli, and connection to the ambitwistor string.