The concept of closed timelike curves allows for time loops from "summary" of Time Travel in Einstein's Universe by J. Richard Gott
The idea of closed timelike curves may sound like something out of science fiction, but it is a concept that has serious implications in the realm of theoretical physics. Essentially, closed timelike curves are paths in spacetime that loop back on themselves, allowing for the possibility of time loops. In simpler terms, closed timelike curves suggest that it may be possible to travel back in time and revisit a point in the past. This concept challenges our traditional understanding of time as a linear progression from the past to the future. Instead, it suggests that time could be a closed loop, where events can circle back on themselves. One way to visualize closed timelike curves is to imagine a hypothetical journey through spacetime that brings you back to your starting point in both space and time. This would create a closed loop in which you could theoretically revisit the same moment over and over again. While closed timelike curves are a fascinating concept to explore, they also raise many questions and paradoxes. For example, if time loops were possible, what would happen if you were to go back in time and change something in the past? Would this create a ripple effect that alters the course of history? Or would events simply play out in a predetermined manner, regardless of any attempts to change them?- The concept of closed timelike curves challenges our understanding of time and opens up a world of possibilities for exploring the nature of causality and determinism in the universe. Whether or not time loops are actually feasible remains a topic of debate among physicists, but the concept itself offers a thought-provoking glimpse into the complexities of spacetime.
