High Energy Theory-Dept of Physics - Carnegie Mellon University

Theoretical High Energy Particle Physics

Faculty: Fred Gilman
Rich Holman
Michael Levine
Ling-Fong Li
Ira Rothstein
Lincoln Wolfenstein (Emeritus)

Group Website:  http://www-hep.phys.cmu.edu/theory.html

Group Overview

The last decades have seen exciting progress in high energy physics with the establishment of the Standard Model of the quark and lepton constituents of matter and their interactions. A unified gauge theory of weak and electromagnetic interactions received experimental confirmation through the discovery of the W and Z bosons and a host of other experiments. The strong interactions of quarks and gluons - the constituents of the proton, neutron and other hadrons - are described by a similar gauge theory, Quantum Chromodynamics.

Our group at Carnegie Mellon works to extract predictions from the Standard Model and on the physics that lies beyond it, such as theories with more complicated Higgs sectors and grand unified theories. We're particularly interested in the nature and origin of the symmetries that characterize the interactions and applications that are of astrophysical or cosmological significance.

Member Research Thrusts

Fred Gilman's research is in theoretical particle physics, particularly in understanding the nature of CP violation. He looks to the LHC to provide us with additional sources of CP violation that would explain the dominance of matter over antimatter in the universe and to produce in the laboratory the particles that make up the dark matter. Gilman is leading efforts to create and expand the McWilliams Center for Cosmology. He is a member of the Board of Directors of the Large Synoptic Survey Telescope Corporation.

Richard Holman's  interests center mainly on the interface between cosmology and particle physics with strong interests in the quantum mechanics/field theory involved in inflationary cosmologies.  He is developing a formalism to describe quantum fields in non-equilibrium environments, such as occur during and immediately after an inflationary phase.  He is also involved in trying to understand how current and future measurements of the Cosmic Microwave Background Radiation could detect effects coming from Planck-Scale physics, as well as constructing models that describe the so-called Dark Energy component of the Universe.

Mike Levine is co-director of the Pittsburgh Supercomputer Center. He has developed computational hardware and numerical and algebraic algorithms to perform high order perturbative calculations in quantum electrodynamics.

Ira Rothstein is concerned with using the data from the LHC to explain the origin of mass and the nature of the dark matter.  He has worked on various topics in this field ranging from theories of extra dimensions to calculating Higgs boson production rates.  He has also using quantum field theory to calculate classical gravity wave profiles for inspiralling black holes. He also works on effective field theory techniques to find systematic ways of calculating strong interaction observables at high energies.

Ling-Fong Li's  research interests are in the area of gauge theories of strong, weak and electromagnetic interactions. Current research is concerned with the phenomenology of the standard model of electroweak interactions and possible new physics beyond the standard model, including grand unified theories, and supersymmetric models. Special attention is given to studies of the symmetry laws and the spontaneous symmetry breaking mechanism.

Lincoln Wolfenstein continues to study the phenomenology of weak interactions based upon the ideas of modern gauge theories. Among the problems being considered are neutrino masses, the origin of CP violation, lepton number violation and the solar neutrino problem.