(Knopf, 370 pages, $29.95)
“The multiverse is an idea whose time has come,” said John Gribbin in The Wall Street Journal. Until recently, “the idea that our entire universe might be just one among many universes (perhaps infinitely many) was the stuff of science fiction.” Yet a growing number of theoretical scientists, including the physicist and best-selling author Brian Greene, have now come to view the multiverse as the best explanation we have for both the simple phenomena humans can observe and the deeper natural laws that the scientists believe their mathematic models have captured. As he did in both The Elegant Universe and The Fabric of the Cosmos—which explored string theory and quantum physics—Greene sets out in his latest book to translate difficult science into plain English. He doesn’t completely succeed, but the ideas he trots out will “open up many people’s eyes.”
Fans of Greene’s earlier works will find The Hidden Reality a “significantly more difficult” read, said Janet Maslin in The New York Times. Like Stephen Hawking and Richard Feynman before him, Greene “has a gift for elucidating big ideas.” But for every “earthly reference” to The Honeymooners or South Park that he inserts to help “simplify difficult concepts,” along comes mention of “conformally invariant supersymmetric quantum gauge field theory”—or some other passage that would challenge even the most earnest “armchair physicist.” Readers may find themselves wishing they lived in a parallel universe in which every word of The Hidden Reality “makes perfect sense.” While “that won’t happen in this one,” it’s “exciting and rewarding” to read Greene, “even when the process is a struggle.”
But what if Greene is not the seer his lay readers want him to be? said Charles Seife in Bookforum. Though he barely acknowledges it, the reason he and other string-theory enthusiasts are now touting the probable existence of an “ungodly number” of alternate universes is that their “theory of everything” would collapse if they didn’t. Other scientists have traveled a different path to become convinced that we live in a multiverse, but they’re not talking about the “Byzantine mess” that the string camp proposes. In Greene’s world, there aren’t just an infinite number of exact copies of you reading this review in their own distinct universes, there are an infinite number of imperfect copies of you, too. One of them, no doubt, is currently “stumbling across this sentence,” causing that you to “scratch your head in amazement with your prehensile tail.”