This article from New Scientist about interacting universes is almost exactly the central conceit of my middle readers novel AEGIS. More or less.

And this idea, called the "many worlds" interpretation, raises other problems. Some theorists say it suggests that physicists doing a quantum experiment would find themselves in a random world, such that they would have an equal chance of seeing the bell ring or not ring. But this does not match the well-tested Born rule, which may predict that the bell should ring 70% of the time, for example.

Physicists have attacked this problem in a number of ways. Now Hanson, an economist who also studies physics, is taking a new approach. He argues that these multiple universes are not actually independent, as was thought, but interacting and sometimes destructive.

Quantum theory states that all universes are not created equal - each "parent" universe is much larger according to a particular quantum measure than its later descendants.

Quantum interactions between the universes were thought to be too small to really affect them, but Hanson says the interactions can be significant between universes of vastly different size.

I'm not sure what to make of this, but it's certainly interesting grist for fictional mills. (The original conceit behind AEGIS was actually that the univesre is a phase boundary in four-dimensional space, but the idea evolved along different lines as it progressed, moving into something similar to Hanson's claims in the above article.)