A movie that sends a young Will Smith to kill his older self sounds fun. But there are two big flaws in its logic, says Simon Ings in his latest column Source: https://www.newscientist.com/article/mg24432540-400-will-smiths-action-thriller-gemini-man-falls-into-major-logic-holes/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home…