Inside every atom in the universe, forces are pushing and pulling to keep the atom's fundamental building blocks stuck together, interacting to preserve a delicate energy balance that enables stars to form and life to exist. Right now, we only have an inkling of how those forces work, but that is starting to change. A physics research team from the University of Adelaide is striving to reveal the hidden nature of the theories that make the universe work.
The researchers from the Special Research Centre for the Subatomic Structure of Matter are taking advantage of the new accelerator technologies available at NCI to move their scientific understanding forward. Accelerators, such as Graphics Processing Units (GPUs) and the new Intel Xeon Phi many-core processors, are enabling the team's microscopic simulations. Their work, which involves reconstructing the behaviour of subatomic particles, is impossible to do without calculating all the forces interacting at such a small scale.
For the simulations, the researchers define a four-dimensional lattice representing space and time in order to compute the effects of the strong force on a particle. The strong force, described by the theory of Quantum Chromodynamics (QCD), binds atomic nuclei together, but due to a phenomenon known as quark confinement, cannot be measured directly in an experiment. For that reason, the researchers turn to supercomputing.
Dr Waseem Kamleh, Senior Research Associate at the University of Adelaide, says, "It is impossible to do research in our field without supercomputers. We get a big increase in speed and performance with the new hardware that NCI makes available to us."
In particular, they use GPUs and many-core processors because of their incredible parallel computing capabilities. The calculations for every point within the QCD lattice come in millions of different variants. They can all run simultaneously, and with the data and calculation speeds provided by accelerated systems, move simulations forward in ways that desktop computers simply cannot.
GPUs were originally designed to process data for the pixels of televisions and computer monitors, so they excel at doing a large number of small, discrete calculations very fast. In high-performance computing, more and more researchers are seeing benefits from these new technologies. QCD researchers are some of NCI's biggest users of these specialised systems, and have been since they first arrived on site. In fact, Dr Kamleh has been using GPUs in his research since the mid-2000s.
"It is really great that NCI is investing in these technologies, they are definitely the way forward for computing. The energy efficiency of computing is becoming a big concern, and GPUs have a much higher performance per Watt than any other solution," says Dr Kamleh.
He and his team are now working to optimise their codes to run as fast as possible on the various platforms. The aim for QCD research in the future is to incorporate the electromagnetic force into the calculations as well. This will provide much more accurate results and a much deeper understanding of the complex structure of subatomic matter.
This story was originally published in the 2016-17 NCI Annual Report.