I also haven't read the book, but I have looked at the prologue which Carroll's put online at http://preposterousuniverse.com/eternitytohere/prologue.html http:

I also haven't read the book, but I have looked at the prologue which Carroll's put online at http://preposterousuniverse.com/eternitytohere/prologue.html http://preposterousuniverse.com/eternitytohere/prologue.html; it's encouraging that he says "Many dramatic-sounding statements are contained herein, but I’m going to be as careful as possible to distinguish between three different types: (1) remarkable features of modern physics that sound astonishing, but are nevertheless universally accepted as true; (2) sweeping claims that are not necessarily accepted by many working physicists, but they should be, as there is no question they are correct; and (3) speculative ideas beyond the comfort zone of contemporary scientific state of the art. We certainly won’t shy away from speculation, but it will always be clearly labeled. When all is said and done, you’ll be equipped to judge for yourself which parts of the story make sense." (Of course, inevitably some people will misjudge for themselves, but that's a danger even for rigorous and un-popular science books.) The table of contents at http://preposterousuniverse.com/eternitytohere/contents.html http://preposterousuniverse.com/eternitytohere/contents.html suggests that only ~ 1/4 of the book is dealing with "unproven theories"; again, I haven't read the book so I can't be sure.