From Higgs physics to dark matter searches: a quest for precision

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In 2012 the infamous Higgs boson was discovered at the Large Hadron Collider (LHC) at CERN in Switzerland - a milestone in the history of particle physics. This enigmatic new particle was predicted more than 40 years earlier with the motivation to cure mathematical inconsistencies in the description of matter at the smallest scales. With the discovery of the Higgs boson the so-called Standard Model of particle physics has been completed. It offers a coherent picture of fundamental particles that make up all known matter. However, yet again inconsistencies in the description of fundamental interactions at the highest energy scales remain. These could be cured within various theories beyond the Standard Model. At the same time, astrophysical and cosmological measurements indicate shortcomings of the Standard Model to explain all observed phenomena at the largest scales and earliest times of the Universe. These puzzles are denoted as Dark Energy and Dark Matter - indicating our ignorance about their physical origin. Explanations of these phenomena represent one of the greatest scientific challenges of the 21st century. Since the discovery of the Higgs boson a large-scale campaign in search for hints for physics beyond the Standard Model and for particle explanations for Dark Matter has been sparked at the LHC. Such hints will first manifest as tiny variations with respect to Standard Model predictions in the production probabilities for scattering processes at the LHC. The hunt for these hints represents the proverbial search for the needle in the haystack - with the important additional challenge: we don't know what the needle looks like. Larger and larger accumulated data sets allow to extend the search to higher and higher energy scales and precision. However, in order to fully harness these datasets the experimental precision has to be matched by equally precise theoretical predictions in the Standard Model including intricate quantum corrections. I.e. we have to understand every detail of our haystack to find the needle!My research concerns high-precision predictions and simulations for a broad range of Standard Model processes using perturbation theory to include quantum corrections. These predictions are computationally very complex and require the development of dedicated efficient algorithms and software tools. The focus of my work is the study of a certain class of quantum corrections that become particularly important at large energy scales. The control of these corrections will allow to stress-test the Standard Model at unprecedented levels of precision.