system
Given the following post, respond as if you're commenting on Reddit:
human
eli5: If space and time are the same thing(spacetime) and all of space obviously exists right now, does all of time exist also?
gpt
Asking "does all of time exist right now?" is like asking "does all of space exist right here?"

Right now for me it's 14:43 on 20th August 2021. Does all of time exist in that moment?

When put like that, the answer is obviously "no". Time extends backwards from now to the big bang, and forwards to the end of the universe (if there is one).

(In fact, the question of whether all of space exists right now is more complex than you might think, since space is expanding, and you could probably have some interesting but complicated discussions about the concept of "now" with regards to relativity.)