From memory of listening to this a few times some time ago (caveat: I certainly didn't study the content of this video carefully, but I do understand some signi

From memory of listening to this a few times some time ago (caveat: I certainly didn't study the content of this video carefully, but I do understand some significant context of his work as he sees it reasonably well I think): Deutsch here isn't trying to modify quantum mechanics, he's trying to "interpret" it. He wouldn't use the term "interpret" of course, for excellent and fascinating reasons that I can't quickly cram into an HN post, but you can find them in his book The Beginning of Infinity (I was convinced about this area of what he says in the book, not about everything else he says there -- there's a LOT of stuff in there!). By the way, I don't know whether or not you meant to imply that Deutsch is not a physicist, but he is -- and well known for his work on the fundamentals of quantum physics.