Research Fellows Directory
Dr Arthur Lipstein
University of Durham
My work aims to reveal the underlying mathematical structure of quantum field theory and string theory by developing new methods for computing scattering amplitudes, which are the basic quantities measured by particle colliders like the Large Hadron Collider. Scattering amplitudes also have remarkable mathematical structure which is fascinating in its own right. In particular, the mathematical simplicity which appears in the scattering amplitudes of certain gauge theories suggests that they can be reformulated as string theories. This realization has led to the development of powerful computational techniques using a branch of mathematics called twistor theory, which have led to the discovery of new symmetries and dualities relating scattering amplitudes to null-polygonal Wilson loops. I plan to further develop these techniques by making contact with methods from integrable systems and searching for new mathematical structures in scattering amplitudes such as multiple polylogarithms and cluster algebras. Many of these ideas can be extended to gravitational theories using a recently developed framework known as ambitwistor string theory, which can be thought of as a chiral infinite tension limit of ordinary string theory. Remarkably, certain ambitwistor string theories describe tree-level gauge and gravity amplitudes in four dimensions with any amount of supersymmetry, and there is strong evidence that they can also describe loop amplitudes of maximal supergravity. Furthermore, ambitwistor string theory reveals new infinite-dimensional symmetries of gravitational scattering amplitudes from the point of view of two-dimensional conformal field theory. Ambitwistor string theory is still in its early stages and there are many directions to explore, such as generalizing the framework to loop-level, curved backgrounds, and theories with massive particles. In summary, my research combines many exciting recent developments in the fields of scattering amplitudes and twistor string theory. Ultimately, this approach should provide new methods for computing amplitudes relevant to collider physics as well as new insights into quantum gravity.
Interests and expertise (Subject groups)