High Energy Physics on Blue Waters

Paul Mackenzie, Fermi National Accelerator Laboratory

Usage Details

Carleton DeTar, Steven Gottlieb, Douglas Toussaint, Paul Mackenzie, Alexei Bazavov, Chulwoo Jung, Christopher Kelly

The long term goals of high energy physicists are to identify the basic building blocks of matter and to determine the interactions among them that give rise to the physical world we observe. Major progress has been made towards these goals through the development of the standard model, which encompasses our current knowledge of the fundamental interactions of physics. It consists of two quantum field theories: the Weinberg-Salam theory of electromagnetic and weak interactions, and quantum chromodynamics (QCD), the theory of the strong interactions. The standard model has been enormously successful in explaining a wealth of data produced in accelerator and cosmic ray experiments over the past forty years. However, high energy physicists believe that a more general theory will be needed to explain physics at the shortest distances or highest energies. The standard model is expected to be the low energy limit of this more general theory, and a great deal of the experimental effort in high energy physics is directed towards the search for physical phenomena that will require theoretical ideas beyond the standard model for their understanding.

This project directly supports this effort by carrying out ground-breaking simulations on Blue Waters. In order to understand where the standard model might break down and new physics enter, one must, of course, determine its predictions and compare them with experiment. This is particularly challenging for QCD, the component of the standard model that describes the strong interactions of sub-atomic physics. At present, the only means of extracting many of the most important predictions of QCD from first principles and with controlled errors is through large scale numerical simulations of the type that will be carried out on Blue Waters. These simulations play an important role in efforts to obtain a deeper understanding of the fundamental laws of physics.

In terms of broader impacts, the project has a long standing policy to make the large data sets—gauge configurations and quark propagators—produced and codes developed publicly available. Based on past experience, the project anticipates that the data sets and codes created for the project will be used by others in a wide variety of calculations important in high energy and nuclear physics.

Furthermore, lattice QCD has been a fruitful training ground for doctoral and postdoctoral students. Those entering the field must obtain a broad knowledge of computer hardware and software, in addition to a solid background in physics. As a result, scientists trained in this field have a wide range of employment opportunities inside and outside of academia. There are approximately seventy-five young scientists in training in this field in the United States at the present time. Some will benefit from working on the project, and many more from the code and data sets produced by it.