Self-tying shoes Self-tying shoes Self-tying shoes (also known as "self-lacing" or "power laces") are designed to automatically tighten once the user puts them on. Such shoes were initially depicted in the 1989 science fiction film "Back to the Future II". In April 2009, Nike filed a patent for self-lacing shoes, with a design that bears a resemblance to those worn by Marty in the film "Back to the Future II", raising speculation among fans about a possible debut of self-lacing shoes. In 2014, Tinker Hatfield, the designer of the original Nike shoes as depicted in "Back to the Future II", indicated that
Time travel physics. According to the philosophical theory of compossibility, what "can" happen, for example in the context of time travel, must be weighed against the context of everything relating to the situation. If the past "is" a certain way, it's not possible for it to be any other way. What "can" happen when a time traveler visits the past is limited to what "did" happen, in order to prevent logical contradictions. The Novikov self-consistency principle, named after Igor Dmitrievich Novikov, states that any actions taken by a time traveler or by an object that travels back in time were part of