For the first time, astronomers have observed a strange quantum phenomenon in action, where a neutron star is surrounded by a magnetic field so intense, it’s given rise to a region in empty space where matter spontaneously pops in and out of existence.
Called vacuum birefringence, this bizarre phenomenon was first predicted back in the 1930s, but had only ever been observed on the atomic scale. Now scientists have finally seen it occur in nature, and it goes against everything that Newton and Einstein had mapped out.
“This is a macroscopic manifestation of quantum field,” Jeremy Heyl from the University of British Columbia in Canada, who was not involved in the research, told Science. “It’s manifest on the scale of a neutron star.”
An international team of astronomers led by Roberto Mignani from INAF Milan in Italy made the discovery while observing a neutron star called RX J1856.5-3754 that’s 400 light-years from Earth.
Neutron stars are the crushed cores of massive stars that collapsed under their own weight when they ran out of fuel, and exploded as a supernova.
They’re made of some of the most dense material in the Universe – just 1 teaspoon of the stuff would weigh 1 billion tons on Earth – and their crust is 10 billion times stronger than steel.
Neutron stars also have the strongest magnetic fields in the known Universe – astronomers predict that the strongest neutron star magnetic fields are nearly 100 trillion times stronger than Earth’s.
In the empty space near the incredibly intense magnetic field of a neutron star, quantum virtual particles are ‘excited’, and they have a dramatic effect on any photons passing through.
“According to QED, a highly magnetised vacuum behaves as a prism for the propagation of light, an effect known as vacuum birefringence,” Mignani explains in a press release.
“This effect can be detected only in the presence of enormously strong magnetic fields, such as those around neutron stars,” adds team member Roberto Turolla from the University of Padua in Italy.
Researchers directed the world’s most advanced ground-based telescope, the European Southern Observatory’s Very Large Telescope (VLT), at their neutron star, and observed linear polarisation – the alignment of light waves influenced by electromagnetic forced – in the empty space around the star.
What would it feel like to pop in and out of existence? Perhaps you are doing it right now. How would you know?