Their finding could open a "new cosmic window" in quantum physics and improve understanding of the universe, according to research published in the international journal Nature on Thursday. "We have observed quite a few magnetars ... that have these extremely powerful magnetic fields that should produce this vacuum birefringence effect. Dr Lower said the study put physics to the ultimate test, possibly revealing more about the mysteries of the universe. "Our best theories of quantum electrodynamics and quantum physics all still work when you put them in the most extreme magnetic environment in the universe," he said. "It's a bit of a relief because it means that our theories still work and there's nothing broken with physics.