eli5 How does/can space expand?
In: 2
[This is a great overview of the expansion of the universe](https://youtu.be/9DrBQg_n2Uo)
I also recommend PBS Spacetime, Sabine Hossenfelder, Arvin Ash, and Cool worlds. They all cover physics topics very well even if you don’t have a strong math background.
We don’t really know.
Observationally we can see that it does, but the underlying mechanism has remained a mystery. Whatever energy is driving the expansion is undetectable through any known means.