In a groundbreaking discovery, scientists have revealed an unprecedented map of the forces acting within a proton. This map offers a glimpse into the intricate dance of quarks—the fundamental particles at its core—when struck by high-energy photons.
This remarkable achievement stems from an international collaboration, including researchers from the University of Adelaide, who are on a mission to unravel the mysteries of sub-atomic matter and the forces that govern the universe.
Using a cutting-edge computational approach called lattice quantum chromodynamics (LQCD), Associate Professor Ross Young of the School of Physics, Chemistry, and Earth Sciences and his team have managed to create the smallest-ever force field map of nature.
“LQCD allows us to break down space and time into a finely-tuned grid,” said Associate Professor Young. “This enables us to simulate how the strong force—the glue that holds quarks together inside protons and neutrons—behaves across different proton regions.”
The findings showcase the immense forces within the proton, reaching an astonishing half a million Newtons—comparable to the weight of 10 elephants—compressed into a space far tinier than the nucleus of an atom. University of Adelaide PhD student Joshua Crawford led the charge in calculations and spearheaded the study alongside his mentors and global collaborators.
“These maps of internal forces provide a new window into the workings of the proton,” explained Crawford. “They help us understand its behavior in high-energy experiments, such as collisions at the Large Hadron Collider (LHC), or studies that probe matter’s most fundamental structure.”
The LHC is the world’s largest particle accelerator, a marvel of modern science and technology. CERN built it in collaboration with over 10,000 scientists worldwide. The LHC serves as a testing ground for theories in particle physics, pushing our understanding of the universe to its limits.
Drawing inspiration from history, Associate Professor Young commented, “Edison didn’t invent the light bulb by focusing on brighter candles. He built upon centuries of work on light and matter. Similarly, our research peels back the layers of the proton’s behavior under light, advancing our grasp of nature’s most basic forces.”
New force distributions revealed by the calculations, on top of the probability map of finding a quark in the proton. Joshua Crawford / University of Adelaide.
The implications of this discovery go far beyond the lab. Future advancements in technology and medicine, such as proton therapy—a cutting-edge cancer treatment that precisely targets tumors, could benefit from these insights.
“Just as understanding light paved the way for lasers and imaging, this knowledge of protons may lead to innovative breakthroughs,” Young added.
With this unprecedented visualization of the forces within a proton, the scientific community takes another step closer to unlocking the universe’s building blocks, bridging the gap between abstract theories and tangible applications.
Journal Reference
J. A. Crawford, K. U. Can, R. Horsley, P. E. L Rakow, G. Schierholz, H. Stüben, R. D. Young, J. M. Zanotti. Transverse Force Distributions in the Proton from Lattice QCD. Physical Review Letters, 2025; 134 (7) DOI: 10.1103/PhysRevLett.134.071901