19 of 23 people found the following review helpful
This review is from: From Eternity to Here: The Quest for the Ultimate Theory of Time (Hardcover)
Let me first say that I am a huge fan of Sean Carroll. I watched his Teaching Company Lectures on Dark Energy and Dark Matter, I read his graduate text on General Relativity (even after having taken the class and owning Hartle's book on GR), and I follow Carroll's papers/articles.
This book is garbage. I give it 3 stars out of respect for the author and I think that someone who is picking up a popular physics book for the first time will find some value in it. However, the book is poorly written, in my opinion. One would be better served purchasing books by Michio Kaku, Paul Davies, Stephen Hawking and any other writer of popular physics who has demonstrated some kind of connection to the layman.
It is important to mention that this book doesn't even come close to developing a complete theory of time. in fact, there is no new contribution herein made on the subject. Furthermore, I think Carroll bit off more philosophy than he could chew. He claims that entropy gives a necessary arrow of time, but entropy only demonstrates time asymmetry (see "Asymmetry of Time" by PWC Davies and "Direction of Time" by Hans Reichenbach). Also, Carroll fails to achieve awareness of the philosophical import of some of the statements he makes, such as the 2nd Law of Thermodynamics acts as the arrow of time, necessarily moving events forward. The problem here is that the current description of this natural phenomenon is statistical, which means that the local ordering of microstates will occur. What does this mean according to Carroll's interpretation is that time can locally reverse and, one would expect at somepoint, that time would run backwards for no reason sometimes. The necessary addition to the interpretation, as Carroll explains, is that there must exist some underlying physical or metaphysical structure that extends beyond the current mathematical description, a result Carroll would not like given his perspective.
Carroll fails to give us the "why" or the "what" of time. What he does give us is a subpar history of physics and its association with time, as well as a 375 page book that could have been written in 150 pages.