I was watching a video (https://www.youtube.com/watch?v=muJYTeQlvC4) where the director of a videogame company speaks about one of its most successful games. This game is set in a floating city which would have "windows" to other parallel or alternative universes. Around minute 2:35, he refers to these multiple universes and mentions that, in reality, Werner Heisenberg was one of the proponents of these multiple universes.
But is this right? I have not been able to find any reference or quote by Heisenberg that indicates that he was happy with the idea of having multiple universes.
So, is this right? Did Werner Heisenberg ever agree or propose the existence of some kind of multiverse?