Causality is interesting. It's a simple concept, Cause, and effect. Often When people think of causality They are really thinking of Retrocausality, also called retro-causation or retro-chronal causation, Basically any of several hypothetical processes that reverse causality. But Causality get's complicated when one enters into alternate timelines. There are theories that Every time we make a decision we are presented with options and each option is a different timeline that can and does play out fully via causation, Simple cause, and effect. I don't feel this multiple timeline ordeal paints an accurate description of time. Shock Quantum theory states that information from the future can affect the past and there are experiments that prove as much. SHOCK QUANTUM THEORY: The future is affecting the PAST Follow me on this, If we are actively retro-engineering the past with our actions in the present, Then how are we creating multiple causations in time? It would seem to me time is very flexible and the past accommodates the future by adapting to suit it. Time is Quantum in this way as the past and future are seemingly entangled yet separate enough to distinguish from one another. Honestly, if you think about it, a Quantumly entangled timeline as a whole smashes the necessity of multiple timelines, Maybe doctor who was right, after all, Time is a misshy messy timey whimy goo that is somewhat malleable..