Quantum simulator shows matter emerging from field: 70-year-old calculations don't match

In quantum electrodynamics, the force of interaction between opposite electric charges diminishes as they move apart. The potential energy approaches a constant limit: to separate an electron and a positron to an infinitely large distance requires a strictly fixed amount of work. In quantum chromodynamics, which describes the behavior of quarks and gluons inside atomic nuclei, the interaction is arranged differently. The attractive force between quarks does not decrease with distance but maintains a constant magnitude—about sixteen kilonewtons. The potential energy in this case grows directly proportional to the distance between particles. As a result, the gluon field between receding quarks does not dissipate into space but compresses into a one-dimensional region of high density—a force tube that…