The Theoretical Particle Physics group seeks to understand the fundamental forces of nature and the basic structure of matter, energy, and space-time. Work proceeds on theoretical foundations, such as M-theory and string theory, on the interface of particle physics and cosmology, and on phenomenological studies which test, strengthen and extend the current "standard model". Topics of interest include the string theory description of quantum gravity and gauge fields, supergravity, dark matter and dark energy, big bang physics, the origin of flavor and CP violation, the phenomenology of supersymmetry and string theory, QCD, regularization and renormalization in field theories, and the general connection of theory and experiment. The stimulating environment of the Leinweber Center for Theoretical Physics provides a very active atmosphere, support for visitors in all areas of particle theory, and fruitful cross-connections between the particle group and other theoretical disciplines.
Michigan's experimental groups have lead roles in frontier experiments spanning much of particle and nuclear physics. The ATLAS Collaboration contributed to the discovery of and now is studying the properties of the Higgs boson. At the same time, the group is searching for other new phenomena in 14 TeV proton-proton collisions at CERN's Large Hadron Collider. The Atlas Great Lakes Tier 2 computing center disseminates research data throughout the United States. The Linear Collider group is carrying out detector R&D for a future high-energy electron-positron collider. A large Michigan team works on the Dark Energy Survey telescope which will measure the nature of the "dark energy" that is accelerating the expansion of the universe. The U-M nuclear physics group uses beams of unstable nuclei to understand the astrophysical origin of the elements, while also pursuing studies in radiation oncology and nuclear medicine. The K0TO experiment aims to discover and measure the second order flavor changing neutral current reaction KL → π0νν, which will either establish more precise limits for the standard model or lead to new physics. The standard model predicts that this reaction will have a branching ratio of (2.8±0.4)*10-11, and will occur via the golden decay mode. This experiment aims to capture 100 events at this branching ratio for a 5% η measurement, using a 30 GeV beamline. K0TO involves collaborations between institutions in the United States, Russia, South Korea, Taiwan, and Japan, while the experiment itself is being hosted as project E14 at the Japan Proton Accelerator Research Complex (JPARC) in Tokai, Japan.
Nuclear, particle, and astrophysics at Michigan all benefit from the close relationship between our theory and experimental groups, and all teams look forward to uncovering new knowledge about the fundamental laws governing our universe.