Science Alert  October 13, 2023 Although the existence of closed time like curves is hypothetical, they can be simulated probabilistically by quantum-teleportation circuits. An international team of researchers (UK, Switzerland, USA – NIST, University of Maryland) leveraged simulations to pinpoint a counterintuitive nonclassical advantage achievable with entanglement. A metrologist prepared probes to input into an unknown quantum interaction. The goal was to infer as much information per probe as possible. If the input was optimal, the information gained per probe could exceed any value achievable classically. The problem was that, only after the interaction the metrologist could learn which input […]