No, this topic has nothing to do with the existence of a Universe or Multiverse, so if you were looking for something like that ... Begone!
Everything I will say is rhetorical. All of these are "what ifs". And this topic probably makes no sense and is pointless. But still.
So, the question of this topic is: What would it be like outside of the Universe. What colors (if any)? Would there be light? Or would it be like trying to explain what yellow is to a person who has always been blind?
Please nobody post something like "you can't get outside of the Universe, so hah!" For this purpose I will assume we can.
In another world: All the physics of this universe apply.
In another Universe: The physics could be the same or completely different. Also, there would be no way to reach this hypothetical place unless you use a wormhole or other natural teleportation device (if it even exits.)
There is no telling AT ALL of what another universe is like.
We only know what we seen. Everything there might be out of our system. The impressions that lie within might corrupt our systems. Too complex for us to understand.
