Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime Hardcover – Illustrated, September 10, 2019

I'm late to the party, I know; the book was published almost a year ago. But I swore I wouldn't buy another book on Quantum Theory. Every author claims they will explain it, but of course they can't. All I wanted to do was understand quantum mechanics before I died, but to use an oxymoron, Carroll made it blindingly clear that wasn't going to happen. Not the dying part, the understanding part.Don't misunderstand - this is a superb book. It's well written, insightful, and entertaining. It's on the other extreme of the spectrum of useful explanations from, say Roger Penrose. Penrose is reputed to be one of the smartest living scientists, but his writing is impenetrable and should not be marketed to the general public. Maybe 100 people in the world understand him. I suspect most physicists lie and never finish his books.I knew there was a problem with quantum theory when I tossed the problem of quantum entanglement to my 9 year old grandson and he couldn't solve it. He's a really smart kid. My experience has been the drunker I get the more sense theories seem to make. Problem is, I could never get drunk enough for quantum mechanics to make sense. When I read that if the wave function of the universe simply obeys the Schrodinger equation it will undergo decoherence and branching I think to myself tell me something I don't know. No I don't. I think is this going to be on the test? Is it too late to drop the course? What sustains me is the famous Feynman quote. Don't feel bad if you don't understand quantum physics. Nobody does.But exploring the many manifestations of quantum theory with witty conversations and amusing anecdotes is not enough. String theory, the many worlds, the numerous other quantum theories Carroll explains reminds me of what Hossenfelder said in her recent book Lost in Math. Theoretical physicists are collectively delusional, unable or unwilling to recognize their unscientific procedures. As Unger and Smolin said in The Singular Universe and the Reality of Time, if a theory makes no predictions and is unfalsifyable it's no longer science. The more time that passes after the establishment of the Standard Model in the 1960's and 70's with very little progress, the more philosophical and metaphysical science seems to have become.The thing I can't get past is nonlocality. Neither could Einstein. Having remote particles instantly affect each other when one of them changes is what Einstein called spooky action at a distance. No explanation I've seen is convincing.I think some of the critiques of Carroll's book are a tad harsh. I think the problem lies with quantum physics- trying to explain it is pretty heroic. Despite my criticism, if Sean Carroll writes another book I'll probably buy it.A parting note - I would have submitted this review earlier, but towards the end of the book I was seriously injured by a collapsing wave function.

Many folks have expressed their thoughts about the discussion of the Many Worlds/Everettian interpretation of Quantum Mechanics contained in this book, but I'd like mention another aspect of this extraordinary book.Namely its excellent description of the so-called "Measurement Problem" of QM; that is the exploration of how QM describes the "Realism" (in the technical sense) of the phenomena underlying the results of laboratory experiments. Or, phrased another way, whether such "real" actual objects and interactions actually exist (as denied, for example, by the standard "Copenhagen" interpretation of QM).The discussion of the so-called "Many Worlds Interpretation" is, of course, excellent. And the book should be praised for presenting an intelligent, detailed --and serious-- discussion of the topic, accessible to any thoughtful, careful reader.But to my mind, the book is equally (or, perhaps more) valuable for laying out and explaining the actual underlying questions that underlie this whole topic; moreover, the issue that the "Many Worlds Interpretation" intends to address and, perhaps more to the point, a topic that is almost never seriously addressed even in university courses in QM.(If I may suggest another book that covers much of the same material (i.e. concerning the "Measurement Problem"), but with additional focus on the detailed history of the discussion, the reader may wish to take a look at Adam Becker's "What is Real?")

No dumbing down. This is a well written book by one of the best theoretical physicists in the world. The study of foundational theoretical physics whether cosmology, relativity, astrophysics, or as in this case foundational quantum mechanics by all rights ought to be at the top of all physics research programs at all university’s in the world. I’m sick and tired of hearing about “applied physics.” There is no advancement of human knowledge in “applied physics.” Leave that to the engineers and technologists. By the way all of our great University Doctors in all the basic sciences and liberal arts ought to be the highest paid professionals in the “cosmos”. The only down side to Sean Carroll’s book suffers from the same problem of all other popular books of physics. Please include the equations. You don’t have to derive or manipulate the equations, just present the equations then below each equation show in words how to read each symbol of the equation going from left to right. You would be astonished at what people could learn from just knowing how to read the equations. Often times I get the feeling that physicists and mathematicians are trying to protect their “secret code”. It seems that they really don’t want the general reader, or the educated reader to really understand what they are talking about. I’m not attacking Sean Carroll because he is an amazing writer of theoretical physics, and I thoroughly enjoyed his book, and so I ordered a second copy to share with others.