Two scenes with physic

Good evening,

This might be a dumb question, because I’ve still to touch the physics, but I prefer to ask now, instead of rewriting code later.

I’ve read how to switch between scenes: it seems to fit to one of my specific needs.

But I’ve even seen that one can make the two scenes overlay with each other.

This made me think: what happens if both scenes have the physic enabled?
Do the objects interact between scenes (so messing up with each other when I use two scenes which are intended to stay separated and switch between them) or do they interact only if belonging to the same scene?

In this second case, is the overlay of two scenes supposed to be used to attain some kind of “movie theater” effect, with objects “in the hall” interacting only with other objects “in the hall” and objects “on the screen” interacting only with other objects “on the screen”?

Objects are specific to a scene (when you create an object you pass the scene you want it to be created for) and you can’t use the same object in two different scenes. So everything should work as expected, the two scenes won’t have any interactions.