I focus on fiction, sci-fi, fantasy, science, history, politics and read a lot. I try to review everything I read.
Great ideas and great narration makes this a great audio book. The last quarter of this book has some of the most interesting ideas in physics I have heard. I think these ideas are, by far, the most likely to lead to progress in physics. The first three-quarters is good, but is just a nice rehash similar to a bunch of other speculative physics books covering a brief history of cosmology leading to the theory of inflation and various levels of multiple universes, Boltzmann brains and such, finally culminating in the Measure Problem (one cannot assign consistent probabilities to infinite sets). Then the book gets really interesting! The author proposes that math does not model the universe, but that math IS the universe. The relations defined by a mathematical structure is all that is needed for us to believe all we see and feel is real. Nothing physical is needed. I really thought I was alone in being a strong proponent of this Mathematical Universe idea, so I have quite pleasantly surprised to find this excellent presentation. I was led to my conclusions by a much different path (Bell’s Theorem & Bell Test Experiments) and take these ideas to even greater extremes than Tegmark, but this is the best (the only?) popular presentations of these ideas I have seen.
It may just be awkward editing or just these ideas are heady stuff, but by the end of the book Tegmark seems a bit schizophrenic. He seems to reject continuums and infinities and randomness as unreal (which is what I think), but then he continues to refer to, and use, these as if they were real. Also a good new model in fundamental physics should address multiple issues in physics, but Tegmark does not use his ideas of the Mathematical Universe to clarify the understanding of quantum mechanics (particularly Bell’s Theorem) and the problem linking General Relativity and Quantum mechanics. I think Tegmark underestimated the depth of the Measure Problem. The underlying problem is in any reality, it is simply not possible to take a random sample from an infinite set. Thus any assignment of probability to such constructs is nonsense. Tegmark seems to still be hoping for a resolution of the Measure Problem.
The author has a really pleasant way of covering the history of cosmology, making the story like a mystery novel, using detective work to explain one mystery after another. Yet what makes this book really worth reading is the last quarter where the ideas about the Mathematical Universe are explored. I suspect that in a few hundred years the conception of the Mathematical Universe will be considered the great turning point leading to a final, simple and beautiful, Theory of Everything.
Being a layman interested in quantum theory I found this book important, and even touching. There is trouble with physics and it is wonderful that a very few scientists are pointing it out. I agree with Smolin that the trouble with physics is deeper and more insidious than run of the mill historical scientific dogma. New physicists are being encouraged to research an un-testable theory and actively discouraged from investigating any other underlying foundations of quantum physics. Smolin does not offer any answers, but demonstrates the problem, and encourages more open inquiry. Unfortunately the trouble with physics is very deep. Some of the greatest minds of the twentieth century spent entire careers on open inquiry to understand the fundamentals of physics, yet failed utterly. It is understandable that most advisers, after seeing decades of wasted genius, discourage their gifted students from such pursuits. Yet such pursuits may be the only path to true progress in physics.
This book does not stand on its own really well, it is dependent on having some grounding in the history of quantum theory, so I would suggest reading Lindley’s Uncertainty (and maybe some others), before this reading this book.
Hopefully this book will encourage some unknown non-professional, like Einstein, to ignore the conventional wisdom and see the simple and obvious truth that every professional physicist has missed for a century.
This is a pleasant story of some of the characters and events in astrophysics over the last few decades with a focus on recent data showing the expansion of the universe is unexpectedly accelerating. The characters presented are pleasure to listen to and the level of technical detail is nice for a general audience without being boring to a technical reader. The narration is really good for this kind of material.