For me it is the fact that our blood contains iron. I earlier used to believe the word stood for some ‘organic element’ since I couldn’t accept we had metal flowing through our supposed carbon-based bodies, till I realized that is where the taste and smell of blood comes from.
It’s even crazier because you don’t need to reach the speed of light. It’ll happen in a smaller degree for any speed. Even in mundane conditions.
For example, if your twin spent four days in a 300km/h bullet train, for you it would be four days plus a second.
Usually this difference is negligible, but for satellites (that run at rather high speeds, for a lot of time, and require precision), if you don’t take time dilation into account they misbehave.
(For anyone wanting to mess with the maths, the formula is Δt’ = Δt / √[1 - v²/c²]. Δt = variation of time for the observer (you), Δt’ = variation of time for the moving entity (your twin), v = the moving entity’s speed, c = speed of light. Just make sure that “v” and “c” use the same units.)
I wonder how long it would have taken for us to figure out time dilation in Einstein hadn’t predicted it. I wonder if it would have taken until we observed it with satellites.
Without Einstein, I think that the discovery of time dilation would be delayed by only a few years. There were a lot of people working in theoretical physics already back then; someone else would inevitably dig through Lorentz’ and Poincaré’s papers, connect the dots, and say “waitaminute time might be relative”. From that, time dilation is a consequence.
In special I wouldn’t doubt that Max Planck would discover it.
I’m saying that because, in both science and engineering, often you see almost concurrent discoveries or developments of the same thing, because the “spirit of a time” makes people look at that aspect of reality or that challenge and work with it. The discovery of helium and the development of aeroplanes are examples of that.
Yes I knew about that and I’m glad that doesn’t make it crazier for me, instead it makes it easier to accept. If it were something that happened only after hitting some arbitrary speed value I’d be a lot more mentally damaged