Two-loop amplitudes from the Riemann Sphere

Seminar series

Relativity Seminar

Date

Mon, 03 Dec 2018
12:00

Location

Speaker

Dr Yvonne Geyer

Organisation

IAS Princeton

Massless Quantum Field Theories can be described perturbatively by chiral worldsheet models - the so-called Ambitwistor Strings. In contrast to conventional string theory, where loop amplitudes are calculated from higher genus Riemann surfaces, loop amplitudes in the ambitwistor string localise on the non-separating boundary of the moduli space. I will describe the resulting framework for QFT amplitudes from (nodal) Riemann spheres, building up from tree-level to two-loop amplitudes.