condition can be fulfilled to arbitrary precision in any quantum system described according to relativistic quantum field theory even on spacetimes which do not admit closed timelike curves, casting doubts on whether Deutsch's model is really characteristic of quantum processes simulating closed timelike curves in the sense of general relativity. In a later article, the same authors show that Deutsch's CTC fixed point condition can also be fulfilled in any system subject to the laws of classical statistical mechanics, even if it is not built up by quantum systems. The authors conclude that hence, Deutsch's condition is not specific to quantum physics, nor does it depend on the quantum nature of a physical system so that it can be fulfilled. In consequence, Tolksdorf and Verch argue that Deutsch's condition is not sufficiently specific to allow statements about time travel scenarios or their hypothetical realization by quantum physics. Lloyd's prescription An alternative proposal was later presented by Seth Lloyd based upon post-selection and path integrals. In particular, the path integral is over single-valued fields, leading to self-consistent histories. In popular culture The Final Countdown (1980): A science-fiction time-travel movie in which the aircraft carrier, USS Nimitz, passes through a wormhole back to the eve of the Pearl Harbor. The anomaly returns and sends it back into the present, before it has a chance to affect the outcome. The story The Merchant and the Alchemist's Gate (2007) by Ted Chiang explores the interplay between free will and self-consistent time-travel Steins;Gate (2009): Cited by Makise Kurisu during her presentation on time travel. Harry Potter and the Methods of Rationality: In Eliezer Yudkowsky's exposition on rationality, framed as a piece of Harry Potter fanfiction, Harry attempts to use his Time Turner to influence the past and comes to the conclusion that the Novikov self-consistency principle applies. Orthogonal: A science-fiction novel series that applies the principle. The Netflix series Dark is largely based on the notion that the possibility of time travel tempts the characters to try change the past, which only leads them to cause the events they were trying to prevent in the first place. Outer Wilds (2019): A video game involving time travel which does not follow the principle, causing a game over if the player experiments to test it. See also Causal loop Causality (physics) Chronology protection conjecture Cosmic censorship hypothesis The chicken or the egg Many-worlds interpretation Grandfather paradox Quantum