>>14347443The speed of light is the speed at which reality propagates. Light (ripples in the EM field), just like gravity, moves at this speed because that is basically what's "instant" in this universe. From one region of spacetime to another information can travel no faster. When you look up at the night sky and see a star 1,000 light years away, it's not like you're recieving old information about how the star was 1,000 years ago and that there's secretly some other way to get "real time" information about it. From your frame of reference that is simply how the star is right now. From the Earth's reference frame Betelgeuse simply has not exploded yet.
If you can imagine there being only one dimension of space and one of time, we can define the speed of light as a 45 degree slope on the diagram for convenience. As you move a linear transformation causes the world around you to skew such that the apparent order in which events occur can appear to change depending on distance and time of arrival. When you reach the speed of light relative to the coordinate frame, the amount of skew becomes infinite. Exceed the 45 degree slope and the skew goes negative - you gain the ability to access your own past. Look up the ladder paradox if you want to understand why "the same time" isn't really a concrete thing that exists for two points separated in space.
