High Energy Theoretical Physics

High Energy Theoretical Physics



The Standard Model of particle physics describes how the fundamental constituents of matter (quarks and leptons) interact via the strong, weak, and electromagnetic forces. The strong interaction of quarks is described by the theory of quantum chromodynamics (QCD), while the weak and electromagnetic interactions have been unified into the electroweak theory. Beyond the Standard Model, at sufficiently high energy scales, new physical phenomena are expected to happen. Some of these ideas include grand unification, supersymmetry and various aspects of quantum gravity.

Results from the Tevatron proton-antiproton collider currently running at Fermilab, in Illinois, and the advent of the proton-proton Large Hadron Collider (LHC) scheduled to start running in 2008 at CERN, in Geneva (Switzerland), will boost High Energy Physics into a new era and will provide us with crucial informations to explore the path beyond the Standard Model. Several members of this group are very active in studying aspects of the Standard Model and of theories beyond the Standard Model of direct interest to both present and future colliders.

Owens and Reina perform calculations within the framework of the Standard Model which are then compared with data taken at various colliding beam experiments such as the HERA electron-proton collider in Hamburg, Germany, the Tevatron proton-antiproton collider at Fermilab, in Illinois, and the future proton-proton Large Hadron Collider at CERN, in Switzerland. Active areas of research include higher order calculations in perturbative quantum chromodynamics, and the determination of the momentum distributions of the constituents of the proton and other strongly interacting particles. In addition, calculations are performed pertaining to new particles, such as the hypothetical Higgs boson(s), with particular attention to the application and development of analytical and numerical algorithms for the systematic implementation of higher order pertubative effects in field theory calculations.

Okui's research covers a variety of topics in particle physics and cosmology, such as exploring new mechanisms for electroweak symmetry breaking (a "superconducting" state for the weak nuclear force), analyzing phenomenological implications of supersymmetry, extra dimensions, new strong dynamics, etc., and building models of fermion flavor, neutrino masses and grand unification. He is also interested in searching for new possible signatures that may arise at the Large Hadron Collider.

Large scale computer simulations of particle physics theories are performed by this group. Within the framework of lattice gauge theory as well as in analogue, but computationally simpler spin systems, Berg studies questions of the QCD deconfining phase transitions. This phase transition separates our present day phase of confined matter from a quark-gluon plasma, which was of relevance in the formation of the early universe. Presently the quark-gluon plasma is studied with the relativistic heavy ion collider at the Brookhaven National Lab. Future experiments are planned at CERN.

Bernd A. Berg
Takemichi Okui
Joseph F. Owens
Laura Reina

Find more information about High Energy Theoretical Physics at:
HEP - High Energy Physics.