In a groundbreaking achievement, researchers at the Department of Energy’s Argonne National Laboratory have used the world’s fastest supercomputer to run the most extensive astrophysical simulation of the universe. This simulation, carried out using the Frontier supercomputer at Oak Ridge National Laboratory, simultaneously simulates the physics of ordinary atomic matter and dark matter, marking a significant step forward in astrophysical research. The simulations help scientists understand the complex interactions between gravity, gas, stars, black holes, and galaxies.

The cosmological hydrodynamics simulation models the universe’s evolution, including the formation of cosmic structures like stars and galaxies. These simulations are much more complex and computationally demanding than previous models that only considered gravity. Researchers, led by Salman Habib, director of Computational Sciences at Argonne, explained that the key to these simulations is accounting for gravity’s effects and the intricate behaviors of atomic and dark matter. This comprehensive approach is essential to depict the universe’s evolution accurately.

To perform these large-scale simulations, the team used HACC, or the Hardware/Hybrid Accelerated Cosmology Code, which has been developing for over a decade. The software was upgraded under the ExaSky project, part of the Exascale Computing Project (ECP), which aims to harness the power of exascale supercomputers capable of performing quintillions of calculations per second. With these upgrades, the HACC code ran nearly 300 times faster on the Frontier supercomputer than on its previous platform, Titan, allowing researchers to model vast stretches of the universe in unprecedented detail.

The simulation used around 9,000 compute nodes of Frontier’s powerful AMD Instinct MI250X GPUs, allowing the team to model the universe at a scale that mirrors real-world surveys conducted by large telescope observatories. The results offer new insights into the universe’s structure and are expected to serve as a valuable tool for future research in astrophysics. They will help scientists make more accurate predictions about the universe’s development and improve our understanding of both ordinary and dark matter.

References

• Rumsey, J. & Oak Ridge National Laboratory. (2024, November 25). Record-breaking run on Frontier sets new bar for simulating the universe in exascale era. Phys.Org; Oak Ridge National Laboratory. https://phys.org/news/2024-11-frontier-bar-simulating-universe-exascale.html