I now understand why this book was rated highly by some and lowly by others.
As a hobbyist and not a literalist, there’s only so much quantitative expertise Scarlett Thomas (or I, for that matter) can bring to a discussion of quantum physics, multiple realities and mathematics, and her vague dismissals–by constantly reminding us that protagonist Ariel’s a “Ph.D. in English” and doesn’t fully understand the whole of these concepts–seems lazy at times she means to built tension with relevant, striking injections of information.
But, honestly, I don’t care. The End of of Mr. Y is fun, fast and fraught with terrible existential considerations that allow for whole and multiple universes of tension to play out at different times, while also allowing Ms. Thomas to trigger one revelation after another, slapping the reader (i.e. me) with an onslaught of metaphysical revelation following personal revelation following plot twist in an exciting feat of paralleled controlled/chaotic writing.
Take this story as fiction and get on the ride. It will surely pull you further down its dark portal than you’ll anticipate going.