Annual Report 2017-18
Project Title: The three-loop soft anomalous dimension
In collider particle physics, experiments such as the Large Hadron Collider are achieving ever increasing accuracy. Making best use of this data requires higher and higher precision in the corresponding theoretical calculations. In the experiments we observe the outcome of a collision through a distribution of final states. This requires calculating the scattering amplitude for that process. I will be specialising in the infrared divergences of scattering amplitudes. These divergences are a fundamental property of the theory because it contains massless particles. The IR singularities are associated with soft particles, those with vanishing momenta. These types of divergences actually cancel when we calculate physically observable quantities. However, in the cancellation large logarithmic terms remain. In order to calculate these we need to consider the IR divergences in the amplitudes. This is known up to second order for massive particles. Since we need greater precision in the calculations we need to go to higher orders in the expansion. Recently, there was a breakthrough result at third order for massless particles. In addition, new techniques have been developed for analytically evaluating integrals associated with given processes. The main goal of the PhD will focus on the full calculation of the singularities at third order for massive particles using these new methods.
Awarded: Carnegie PhD Scholarship
Field: Physics and Astronomy
University: University of Edinburgh