Theorie Palaver

Factorization allows us to break a collision into several independent pieces. These pieces are often either universal, such that they can be extracted from another experiment, or are directly calculable from field theory. In this talk I will discuss some of the research projects related to factorization that I have worked and am currently working on, focusing on the study of the track-based energy-energy correlator. I will start by introducing Soft-Collinear Effective Theory (SCET) and discussing how it can be used to derive factorization formulas for collider observables in certain kinematic limits. Next, I will explain what track-based observables are, why track-based measurements are sometimes preferred over all-hadron measurements, and I will introduce the formalism necessary for making track-based predictions. We will then apply this formalism to study energy correlators on tracks. I will explain why energy correlators are interesting to study and what techniques we have used to make our theoretical prediction. I will also compare our result to recently reanalyzed archival ALEPH data, showing excellent agreement between theory and data and paving the way for fits of theory parameters. Finally, if time permits, I will discuss the topic of factorization violation. Here I will discuss whether one can make theoretical predictions for collider observables with a large scale hierarchy where factorization does not hold by studying the leading factorization violating terms.

Upcoming upgrades to the LHC will significantly reduce statistical uncertainties, enabling measurements at percent-level precision. To fully exploit this level of precision, theoretical predictions must achieve comparable accuracy, which requires incorporating higher-order terms in the perturbative series in the strong coupling constant. Currently, only next-to-leading order terms can be included for arbitrary scattering processes, while higher-order corrections remain a significant challenge. A major obstacle lies in the complexity of two-loop calculations for high-multiplicity scattering amplitudes. In this talk, I will overview the modern analytic techniques that have enabled progress on these complex calculations, leading to the first NNLO-precise predictions beyond two-to-two processes. We will explore the current state of two-loop amplitude calculations with multiple kinematic scales and discuss prospects of extending these techniques to a broader class of processes, including those involving massive electroweak bosons and top quarks.