“Scattering Amplitudes in Maximally Supersymmetric Gauge Theory and a New Duality”

Abstract
Scattering amplitudes are the arena where quantum field theory directly meets collider experiments. An excellent model for scattering in QCD is provided by N=4 super-Yang-Mills theory, particularly in the planar limit of a large number of colors, where the theory becomes integrable, and amplitudes become dual to light-like polygonal Wilson-loop expectation values. The first nontrivial case is the 6-gluon amplitude (hexagonal Wilson loop), which can be computed to 7 loops using a bootstrap which is based on the rigidity of the function space of multiple polylogarithms, together with a few other conditions. It is also possible to bootstrap a particular form factor for the chiral stress-tensor operator to produce 3 gluons, through 8 loops. Remarkably, the two sets of results are related by a mysterious “antipodal” duality, which exchanges the role of branch cuts and derivatives. I will describe how the bootstrapping works and what we know about this new duality.

BIO
Lance Dixon is Professor of Theoretical Particle Physics at the Stanford Linear Accelerator Center (SLAC) at Stanford University. There he is faculty member since 1992, after having been assistant professor at Princeton University, where he obtained his PhD in 1986. Since 1995 Dixon is a Fellow of the American Physical Society. He has been a visiting professor at the École normale supérieure, University of Cambridge and at CERN, and received research chairs from the Perimeter Institute for Theoretical Institute in Canada, Humboldt University Berlin, ETH Zürich and the University of Zurich. His research work is very broad, ranging from early influential work about strings on orbifolds and string corrections to gauge couplings to "pathbreaking contributions to the calculation of perturbative scattering amplitudes, which led to a deeper understanding of quantum field theory and to powerful new tools for computing QCD processes.” The latter is the motivation of the Sakurai Prize for Theoretical Particle Physics which he received, with Bern and Kosower, in 2014. His more recent work in phenomenology focuses on precision calculations in QCD, on the formal side he continues being interested in multi-loop properties of gauge and gravitational theories.

Q&A