IBM quantum computer simulates hadronization for first time

A researcher at Lawrence Berkeley National Laboratory used an IBM quantum computer to simulate hadronization, a key process in particle physics.olcf.ornl+1
The simulation modeled how gluon strings snap to form composite particles like protons, a process too fast to observe directly in colliders.phys
Results published in Physical Review D matched classical calculations, laying groundwork for future quantum advantages in subatomic modeling.olcf.ornl

A physicist at Lawrence Berkeley National Laboratory has used an IBM International Business Machines Corporation quantum computer to simulate hadronization — the process by which quarks bind together through the strong nuclear force to form composite particles such as protons and neutrons — marking a step toward quantum computations that could one day surpass classical supercomputers in modeling the subatomic world.

Bridging the Gap in Particle Physics

Anthony Ciavarella, the Berkeley Lab research scientist who led the project, remotely accessed a Heron processor on the IBM Quantum Platform through Oak Ridge National Laboratory's Quantum Computer User Program, leveraging 104 of its 156 qubits to simulate gluon string breaking in one spatial dimension. The results, published in Physical Review D, matched previous calculations performed on classical supercomputers.olcf.ornl+2

Hadronization is central to understanding what happens inside particle colliders like CERN's Large Hadron Collider, where protons smash together at near light speed. The resulting quarks and antiquarks undergo hadronization too quickly to be directly observed, making computer simulations essential for filling observational gaps.ornl+1

"In principle, we know the theory that describes hadronization, but we are unable to make predictions using it because the calculations have been too difficult for a classical computer," Ciavarella said. "On a quantum computer, we should be able to directly make predictions for the details of how hadronization occurs, which will help with the searches for new physics performed at colliders such as the LHC."phys+1

A Simplified Model With Broader Ambitions

Ciavarella employed several simplifications to make the calculation tractable on current hardware: a heavy quark limit, a one-dimensional spatial model, and a technique he co-developed called a "scalable circuit concurrent variational quantum solver" to prepare the qubits in a stable vacuum state. One notable finding reproduced from earlier classical work was that the center of the gluon string appears to behave as though it is gasifying at a finite temperature before snapping apart — a feature that, if confirmed across multiple models, may reflect actual quantum chromodynamics.ornl+1

Looking Ahead

Ciavarella plans to add a second spatial dimension in future work as quantum hardware and algorithms improve. The project, supported by the Department of Energy's Advanced Scientific Computing Research program, is designed to establish the computational templates that physicists will need once larger, more reliable quantum processors become available.olcf.ornl+1

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