Took me a long time to get through this book, but it was strangely compelling despite the density of its concepts. I say strangely because this is a book about physics and cosmology that gets fairly deep into thought experiments, yet Carroll is somehow able to make the reader feel like you understand what the hell he's talking about, even as he wades into black hole event horizons and multiverses. What I most appreciated about this book is that there is a remarkable clarity of thought in the manner complex ideas are conveyed, and Carroll doesn't dumb down material even as he makes it more digestible to lay readers. He wends the narrative of the entire universe around the arrow of time, and this coherency of organizational structure allows us nonscientists to engage with heady quantum theories of cosmology in a manner that is edifying and enlightening.