Newswise — For the last 80 years, the theory of quantum electrodynamics (QED), which describes all electromagnetic interactions, has been a cornerstone of the standard model, withstanding the scrutiny of countless experiments and agreeing with observations down to the smallest known precisions. Yet, some high-intensity scales of QED remain unexplored, prompting some to wonder if quantum computers could deal with these scales’ inherent complexity. Physicists at the University of Illinois Urbana-Champaign are now testing quantum simulations of these so-called strong-field QED (SFQED) processes, recently translating several processes into the language of quantum computing. Their latest work introduces an innovative method for simulating an SFQED process known as polarization flip on a quantum computer, setting a new benchmark for quantum simulations of high-energy phenomena. This research was published in the journal Physical Review D on March 9, 2026, Physics in the strong-field limit For the most part, QED is a well-understood theory. Its predictions agree so well with experiment that it has enabled scientists to make accurate predictions down to within one part per trillion, comparable to predicting the Earth’s diameter to within a fraction of a human hair. This has earned QED its reputation as one of the most accurate theories in science. There are some scales, however, at which QED has seldom been put to the test. “We understand QED pretty well in vacuum and for small numbers of particles, as well as various classical regimes,” said Illinois Physics Professor Patrick Draper, who led the research team. “But there are some high-intensity regimes where we just don’t know what happens.” In these SFQED regimes, electromagnetic fields can soar to strengths quadrillions of times greater than those found on Earth, giving rise to strange physics: photons can scatter off each other, spontaneously decay into matter, and even pop out of