## Theoretical Particle Physics

Radja Boughezal

Radja Boughezal's research interests cover many area of particle physics, including QCD and electroweak precision observables, Higgs phenomenology, and new calculational techniques for precise predictions of collider observables. Most results from experimental particle physics are currently well described by the Standard Model. It encompasses the electromagnetic, weak and strong interactions and has been successfully tested to an impressive level. Our main tool in obtaining verifiable predictions based on this model is perturbation theory. Leading-order results in the Standard Model do not provide a satisfactory description of experimental data; higher order quantum corrections are needed. The work of Radja Boughezal focuses on developing new analytical and numerical calculational techniques to obtain such high-precision predictions for collider observables within the Standard Model and its possible extensions. Email Radja Boughezal

# JJ Carrasco

Physicists use the framework of relativistic quantum field theory to describe how a quantum universe can interact and evolve in a manner consistent with the observed symmetries of space and time. The members of the A&I effort study these theories, often by looking for new ways of extracting special types of predictions called scattering amplitudes. Scattering amplitudes distill these theories to their invariant predictive core in certain circumstances like those of high energy collider experiments. This effort's collaborative studies have led to the discovery of hidden structures that relate and begin to unify understanding of seemingly distinct theories like quantum chromodynamics (governing the strongest known interactions) and gravitation in the form of Einstein’s general relativity (governing the weakest). These new ideas and approaches have application in particle physics, cosmology, gravitational wave astrophysics and quantum gravity.

André de Gouvêa

It is the goal of High Energy Physics to study matter at the smallest distance scales, in an attempt to uncover the fundamental building blocks of Nature and understand their dynamics. The members of the high-energy theory group concentrate their research efforts on the phenomenology of quantum chromodynamics and electroweak interactions, and on understanding the mechanism of electroweak symmetry breaking and the origin of neutrino masses and fermion mixing. Work is carried out in probing the physics that lies beyond the standard model, including supersymmetric theories and theories with extra dimensions. There is also significant activity related to understanding flavor physics, especially heavy quark physics and the physics of neutrino oscillations. Email André de Gouvêa

Ian Low

Ian Low has worked on a variety of topics in theoretical particle physics, including resumming large logarithms in decays of B mesons, models of electroweak symmetry breaking, and phenomenology of dark matter. More recently he has been focusing on physics of the Higgs boson, which is postulated to be the origin of mass of all known elementary particles, and of the dark matter, which makes up the majority of the mass we observe in the Universe. For Higgs related projects he is looking into ways of detecting the Higgs boson, as well as understanding its properties, at the Large Hadron Collider, while the dark matter projects study various possibilities to illuminate the nature of dark matter. Email Ian Low

Frank Petriello

Frank Petriello pursues a research program in precision QCD in order to improve the Standard Model predictions for important hadron collider ob-servables and their backgrounds. He has developed a variety of novel techniques to facilitate the ultra-precise comparison of theoretical predictions with experimental data. A second goal of his work is the development of new strategies to search for and study new physics at the Large Hadron Collider and in other experiments. Email Frank Petriello