When I was a mere lad, I was a physics major, which involved taking a few quantum mechanics courses. And from them I learned that at the quantum level, things get weird. It's difficult to pin things down; the mere act of trying to pin things down causes those things to behave differently than they would otherwise.
But (somehow) things remain sane at the macroscopic level. Why is that? Shouldn't they be weird all the way? At what point, precisely, do they stop being weird?
What I learned was the standard "Copenhagen Interpretation" (CI), cooked up at the very beginning of the quantum era by folks like Neils Bohr and Werner Heisenberg. Which has had great success in explaining things and allowing the design of multiple goodies in our technological wonderland. But over the years, a (relative) few people have had problems with the CI, even starting with Einstein.
Briefly, the CI says: solve Schrödinger's equation, get a probability distribution, and that's about the best you can do. For example, instead of little ball-like electrons orbiting around an atomic nucleus like beads on wires (as seen in The Big Bang Theory), all you get is a probability cloud: chances are good the electon's here, not very good over there, nearly zero over here.
But the naysayers say: wait a minute. What's really going on? The CI says that's, essentially, a meaningless question; there's no way to know. And yet, there have been efforts over the years to "do better". This book champions the naysayers, essentially arguing that (despite its successes) the CI is the Danish Emperor With No Clothes. The author, Adam Becker, deftly outlines the history, biographies of the various characters involved, and some experiments that folks do that favor alternate interpretations over CI.
So, interesting book. Could have done without the authorial cheerleading. Wherever possible, the motives and psyches of the CI adherents are impugned. (Example: within the space of four pages, Becker tells us three times that Heisenberg was concerned that his theoretical efforts would be "eclipsed" by those of Schrödinger. OK, Adam, we get it. Maybe buy a thesaurus for your next book.)
The main objection to the CI seems to be aesthetic; those of an anti-CI bent really don't want to think like that, preferring to think in terms of electrons really being shiny little balls. Becker argues forcefully that way, but has a hard time getting over the plain fact that the CI works just fine: it comports with experiment, sets the basis for fruitful research. Yes, the future could unseat it, but it will have to be on stronger grounds than provided here.