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
Quantum mechanics of time travel the negentropy and computational power diverge as the noise term goes to zero, complexity class may not be the best way to describe the capabilities of time machines. Bennett et al. have pointed some of the problems which arise when unitarity breaks down and quantum evolution becomes nonlinear. Quantum mechanics of time travel Until recently, most studies on time travel are based upon classical general relativity. Coming up with a quantum version of time travel requires us to figure out the time evolution equations for density states in the presence of closed timelike curves (CTC). Novikov had conjectured that once