I was reading a description of the many-worlds interpretation and it stated that the separate universes cannot interact with each other. But in the double slit experiment isn't the interference pattern that is seen when both slits are open, specifically caused by this interference? How can the author state categorically that continuing interference cannot occur? Perhaps it still occurs but we are simply unaware of it. Just as the other universes are still there, but we can no longer see them. Wouldn't entanglement mean that the separate universes are in some way still connected. Or does entanglement and thus interaction, necessarily cease when coherence or whatever it is breaks down. I understand that we no longer see evidence of it, but does that disprove the possibility? I don't know a lot about physics, but this statement puzzled me, and I was hoping that someone could explain it. Thanks in advance for your patience in answering my question.