If it doesn't fundamentally change quantum mechanics as a theory, is the picture likely to turn out fundamentally different from MWI? Roger Penrose, a vocal MWI critic, seems to wholeheartedly agree that QM implies MWI; it's just that he thinks that this means the theory is wrong. David Deutsch, I believe, has said that he's not certain that quantum mechanics is correct; but any modification of the theory, according to him, is unlikely to do away with the parallel universes.

QBism, too, seems to me to essentially accept the MWI picture as the underlying ont... (read more)