Elaboration:
Imagine Spacetime as a movie film reel. All of time (past, present, future) exist at the same time just like all the frames of that movie exist on that reel. If you want to time travel you go to the frame location on that reel. That location we call a WHEN but it is also a WHERE on the reel. Also, when physicists state that time and space are interwoven a film reel analogy encapsulates that theory well. So, time travel could be simply going to a specific coordinate in Space.
Theoretical Physicist Sean Caroll uses the film strip analogy in this video:
Sean Carroll Explains Presentism and Eternalism
See also:
https://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time)
The illusion of time : past, present and future all exist together
Is Time A Single Block? Eternalism And The Andromeda Paradox
Time: Do the past, present, and future exist all at once? | Big Think
Disclaimer: Obviously, I have been watching too many Youtube videos and none of the concepts are my own. But I did think of the WHERE VS. WHEN regarding time travel analogy as I haven’t seen anyone state it that way yet.
Hmmm, wondering if Eternalism is even a necessary component here.
If we take spacetime as a 4 dimensional continuum, then I would just reword this as: “when” is just a specific version of “where” that refers to the time dimension.
Relatively literally means that the difference between when and where depends on your reference frame.
Inside black holes time becomes space, the reason it’s impossible to avoid falling to the singularity once inside is the same reason it’s impossible to avoid tomorrow.