What happens in other universes?
Physicists have contemplated different levels of multiverse
Level 1 What happens inside this universe?
Everything that happens in the observable universe is repeated an infinite number of times. Also, every possible combination of events can unfold an infinite number of times. There are planets where you don’t exist, but also those where you do and you’re the ruling monarch of the universe or a sentient slug.
Level 2 What happens inside this universe?
Most agree that the laws of physics and the properties of particles would differ in each universe. The majority would be unlike ours, but there will be exact copies, meaning lots of identical yous. Others will be near copies in which famous historical events unfolded differently.
Level 3 What happens inside this universe?
As each new universe branches off from a previous one, the laws of physics are consistent across the Level 3 multiverse. However, it’s a one-way journey. You’re forever marching onwards and cannot return to a universe you were in previously, so no time travel to the past.
Level 4 What happens inside this universe?
The creators of the universe have set it up. Perhaps they have experimented with the strength of forces and masses of particles until they found the right settings in order to create a universe with stars, planets and life. There would be no connection between universes in this scenario.