>On Earth, with Newtonian physics, we intuitively think that "now" is shared, so we really can say "I wonder whether someone has scored a goal now," and the answer shouldn't depend on whether you're in a car or not.
That's insightful, and actually it made me realize that it's probably true that nowadays we expect information to be available worldwide effectively instantly, but that obviously wasn't always the case. "Right now" we're having this discussion on Hacker News with people from around the world, but merely a few decades ago this type of simultaneity wouldn't have been possible. Nothing of what would could've done locally could've immediately influenced dozens of people around the globe.
This shared "now" is effectively a modern invention.
I think the unusual part is that it is not a limit of communication, it is time itself. With a tape, you know that it happened in the past, for this, both are experiencing their real present time, but they don't agree with each other.
That's insightful, and actually it made me realize that it's probably true that nowadays we expect information to be available worldwide effectively instantly, but that obviously wasn't always the case. "Right now" we're having this discussion on Hacker News with people from around the world, but merely a few decades ago this type of simultaneity wouldn't have been possible. Nothing of what would could've done locally could've immediately influenced dozens of people around the globe.
This shared "now" is effectively a modern invention.