[h45x1]

[Show HN] Admittedly much less visually engaging :), but some time back I was interested in the twin paradox, so I made a website where you fly a toyish spaceship between three stars and see how the various clocks and the space itself change. It's flat spacetime, so relatively easy to simulate and everything just runs in JS: https://twinparadox.org

The original motivation was, can one make a game with relativistic spaceships, conceptually speaking? The issue is that if a player calls another player IRL it'll be like instantaneous communication... In flat spacetime, though contradictory to its postulates, one can choose a preferred frame of reference, say the planets, and allow instantaneous communication within that plane, not leading to any inconsistencies in a game, I think. Curved spacetime doesn't admit a notion of simultaneity, so that's completely out, no black holes in a game :( Never really got to the point of modelling multiple ships though, the life caught up. So it's just a single ship on the website for the moment.