“That there’s an infinite number of universes sounds more complicated than there being one,” Prof Cox told the programme.

“But actually, it’s a simpler version of quantum mechanics. It’s quantum mechanics without wave function collapse… the idea that by observing something you force a system to make a choice.”

Accepting the many worlds interpretation of quantum mechanics means also having to accept that things can exist in several states a the same time.

But this leads to another question: Why do we perceive only one world, not many?

Brian Cox: ‘Multiverse’ makes sense

Read more "Brian Cox: ‘Multiverse’ makes sense"