A research team led by faculty at the Duke Quantum Center (DQC) has made a significant breakthrough by observing string-breaking dynamics related to particle-antiparticle formation on a quantum simulator. This is among the first such observations in quantum physics and was published in the journal Nature Physics. The study shows that trapped-ion quantum computers can be used to explore deep questions about the universe. The experiment simulated a phenomenon called string-breaking, where two connected fundamental building blocks of matter stretch apart, accumulating energy until new particles form when the connection snaps. This research was conducted by an international team from institutions including the University of Maryland, Oxford University, and others. Their findings join two similar studies by other groups that simulated the same phenomenon using different types of quantum computers. Quarks, the fundamental building blocks of matter, are never found alone. They exist only when bound together inside particles like protons and neutrons. These particles are about a billion times smaller than an atom and cannot currently be observed directly. Imagine two tiny charged particles connected by a taut string—they naturally want to stick together, so it takes a lot of energy to pull them apart. Once they are forced apart, the energy stored in the connection can be enough to create new particles, as mass and energy are directly related through Einstein's equation E=mc². When this happens, the "string" snaps, resulting in two or more pairs of particles instead of just one. However, this process requires immense energy, so it only occurs in extreme environments such as the Large Hadron Collider or the aftermath of the Big Bang. In the new study, the team led by the DQC observed a similar string-breaking process on a trapped-ion quantum platform. Quantum simulators are highly controllable systems that can be programmed to mimic real-world processes at atomic or subatomic levels. The researchers encoded a string-breaking model into a chain of 13 trapped ions and used precisely controlled laser beams to adjust the interactions among the ions. These interactions mimicked the stretching and eventual breaking of a string. By placing the system in an out-of-equilibrium state and tracking its changes over time, the researchers observed the emergence of effective charges and reconstructed the dynamics of the string. They also simulated the process on a classical computer and confirmed the results were accurate. However, as the complexity of such problems increases, only quantum computers will be able to handle them, unlike classical computers. Other research teams have also simulated the string-breaking process using different quantum computing platforms. Google and QuEra Computing, for example, recreated the phenomenon using superconducting circuits and neutral atoms, respectively. Each platform has its own strengths and challenges. According to Christopher Monroe, a professor at Duke and leader of the research, these three platforms—trapped ions, superconducting circuits, and neutral atoms—are currently leading the field in quantum computing. The results from the trapped-ion platform represent a step toward creating quantum simulations so complex that they surpass even the most powerful supercomputers. These simulations could one day help scientists explore fundamental questions about the universe, such as how matter evolved after the Big Bang.