Long-sought phenomenon finally detected
Part of a 1929 prediction by physicist Hermann Weyl — of a kind of massless particle that features a singular point in its energy spectrum called the “Weyl point” — has finally been confirmed by direct observation for the first time, says an international team of physicists led by researchers at MIT. The finding could lead to new kinds of high-power single-mode lasers and other optical devices, the team says. For decades, physicists thought that the subatomic particles called neutrinos were, in fact, the massless particles that Weyl had predicted — a possibility that was ultimately eliminated by the 1998 discovery that neutrinos do have a small mass. While thousands of scientific papers have been written about the theoretical particles, until this year there had seemed little hope of actually confirming their existence. “Every single paper written about Weyl points was theoretical, until now,” says Marin Soljačić, a professor of physics at...