The Geometry of Causality

But why do intelligent people want to believe that any such coherent stories can actually be told in real life? We all know it's impossible. Even basic questions such as "How old are you" become unanswerable. Really intelligent informed people know the relative scales involved. So if all of Star Wars were re-imagined to occur using reasonable tech within the several cubic light years around Alpha Centauri, no speeds where severe relativistic time dilation effects are necessary for normal transportation. "How old are you" is readily answerable +/- a month for just about everyone, even most spacefarers. Heck, even the prequel trilogy makes more sense. (As Plinkett puts it, why are people on the planet of Naboo dying because they lack, "Space Supplies?" It would make a whole lot more sense if Naboo were an icy ball in the Oort cloud.) A person gets in a ship and travels at 1 G to another star, then turns around and comes back to Earth, they've aged 20 years, meanwhile on Earth 200 years have passed and all their friends are dead. Which timeline is real? How would any sci-fi tropes play out, in real life, in a universe of such inconsistencies? Another thing: I'm not an expert myself, but I can already tell that you don't even understand the big abstractions of relativity that well. The "Twin Paradox" is not actually a paradox. There is a global set of spacetime intervals which is consistent among all observers. It's only each observer's view of the spacetime interval which disagr

> If there's anything the universe is, it's Eventually Consistent. Please disregard this inconsistency guff! The Universe isn't Eventually Consistent. It's simply consistent. What's really going on, is that some programmers don't understand relativity. Relativity doesn't actually say that everyone gets their own reality. There is a consistent consensual reality. Spacetime intervals are consistent between all observers. The time ordering of events changes depending on the observer's POV and relative motion, but there is an underlying consistent reality that's the same for everybody. [link] [this video] The "Spacetime Globe" by Minute Physics is the most helpful thing I've seen, flat out, for understanding relativity. > Knowledge of events in our universe is like an immutable, append-only database This is correct. Relativity just says that different users get different results, depending on how they query. The underlying database is the same for everybody. (Some parts of it are forbidden access, of course.) Programmers have been causing physicists to facepalm since at least the USENET days. I should know. I was one of them!