First time-travel movies are loopers

摘要

Take that, Hollywood. You may have grappled with time travel for decades, but now that physicists are in on the action, they have the first movies of what travelling to the past actually looks like. The visualisations are surreal, the result of the shape of a hypothetical universe in which time travel is possible. They might help us understand the origins of causality, which is still shrouded in mystery, and pave the way to physical, table-top models of time travel.