I do not think there is a simple way to illustrate the bounds and limits of time-space at the light of the theory of relativity.

For who might be interested there is this voice on
Wkipedia that might give a succint introduction. It immediately becomes abstract and mathematical.
Either one knows or not.
Speculating about it in a SF context, that can be a lot of fun, and also to reflect on the perception of time, both personally in the flow of our life, and historically, how time was conceptualized, before about 100 years ago.