Entangled quarks seen for first time

For the first time, scientists have observed quantum entanglement — a state in which particles intermingle and can’t be described separately — in fundamental particles called top quarks. Physicists had no reason to suspect that quarks wouldn’t allow themselves to be entangled, but researchers say this measurement, achieved by analysing over 1 million pairs of quarks created in collisions between protons, could pave the way for future high-energy tests of the phenomenon.