US uses world’s first exascale supercomputer to model supernovae, fusion reactors

US scientists have turned to the world’s first exascale supercomputer, the Frontier, to unlock magnetic turbulence in plasma, widely regarded as one of physics’ most stubborn problems. Researchers at the Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL) used AI models to train the world’s third fastest exascale supercomputer to precisely capture the chaotic behavior of plasma. According to the results, the find could greatly reshape research and improve the way scientists model supernova explosions. It could also help build more efficient nuclear fusion reactors. “This kind of capability has long been the dream of astrophysicists and many other scientists,” Eliu Huerta, PhD, a computational scientist at Argonne National Laboratory who oversaw the study, said. “It’s the first time this level of insight via AI has been achieved for systems of this complexity.” Modeling cosmic explosions Magnetohydrodynamic (MHD) turbulence is a complex and chaotic process, that governs how electrically charged gases (plasmas), behave under the influence of magnetic fields. These turbulent flows are found throughout the universe. They shape solar flares, supernova explosions , and even Earth’s own magnetic environment. However, accurately modeling MHD turbulence has remained a great challenge. Traditional methods, like the Reynolds-Averaged Navier Stokes (RANS) approach, rely on simplified equations that smooth out fine details, and fail to account for all relevant physics. “The more chaotic the system, the harder to simulate it,” Huerta noted. To tackle the challenge, the scientists came up with a two-stage approach. First, a physics-informed neural operator learns the behavior of plasma, while mapping how the system evolves over time. Then, a diffusion-based model steps in to reconstruct the finer details, therefore regenerating the small eddies and rapid fluctuations that define turbulent flows. But, training the models to generate thousands of detailed plasma simul…