<i>What was missing from the discussion was an attempt to tackle one of the issues that plagues string theory: the math may all work out and it could provide a convenient way of looking at the world, but is it actually related to anything in the actual, physical Universe? Nobody even attempted to tackle that question.</i><p>I was surprised and happy to read this part. With my multiple attempts (and mostly failing) to understand quantum mechanics or string theory, I got the impression that this topic is never approached, and that omission never explained. If you're going to try to convince someone that our universe has multiple parallel futures, you should be ready to explain how that relates to our lives.<p>I think that's what lead me to the <i>impression</i> - as an <i>outsider</i> - that fascinating sounding things like the many-worlds interpretation are beautiful ideas that do not exist outside of equations, they're a kind of science fiction, a kind that is backed by mathematics and published in journals.