Brian Greene: Back to blow your mind.
Having explained string theory to the masses in his bestseller The Elegant Universe and untangled the fabric of the cosmos in The Fabric of the Cosmos, the superstar physicist returns this month with The Hidden Reality, an ode to multiverse theory.
By now, the 11-dimension string theory models of his earlier books … are looking downright commonsensical. “The Hidden Reality” moves on to increasingly speculative and exotic discussions of a bubble multiverse (“Think of the universe as a gigantic block of Swiss cheese. …”) a holographic one, a brane-world scenario (courtesy of string theory), computer-driven simulations, questions of how probability relates to infinity, and the Many Worlds view of quantum mechanics. “A frequent criticism of the Many Worlds approach is that it’s just too baroque to be true,” Mr. Greene writes. [The New York Times]
Multiverse theory—the idea that our universe and its Big Bang were just one of many—is a favorite theme of science fiction (and “Family Guy”), as it allows us to have parallel selves in parallel universes. Greene explains the real science behind the idea with one of his litany of analogies: a simple deck of cards.
If you shuffle the deck infinitely many times, the card orderings must necessarily repeat. Similarly, in an infinite expanse of space, particle arrangements must repeat too—there just aren’t enough different particle configurations to go around. And if the particles in a given region of space the size of ours are arranged identically to how they are arranged here, then reality in that region will be identical to reality here. Except that maybe we’d be seeing the Jets and the Bears in the Super Bowl. [Wall Street Journal]
Once the basics of the multiverse are grounded in physics, Greene ponders a little philosophy. After all, not everyone is comfortable with the idea of infinite versions of themselves living out every conceivable path somewhere.
No flight of fancy, however wild, is denied existence. Every potential aspect of one’s character, suppressed in this universe, finds manifestation elsewhere. Bad fates in this universe are avoided in an infinity of others. And the multiverse settles all perplexing questions of “Why this?” with a simple, “Because we see only one thread of an infinite tapestry.” [Salon]
The Hidden Reality wins high marks with most reviewers, who praise Greene’s accessible treatment of an arcane cosmic subject. But not all. For some, like Scientific American‘s John Horgan, Greene’s taste “for the expansive” carries him too far out into the great abstract beyond.
My beef with Greene is this: He has become a cheerleader for the descent of theoretical physics into increasingly fantastical speculation, disconnected from the reality that we can access empirically. Greene has argued eloquently for the plausibility of string theory, which … postulates the existence of particles that are far too small to be detected in any conceivable experiment. [Scientific American]
So read The Hidden Reality to reach your quota of “whoa.”
DISCOVER: Science’s Alternative to an Intelligent Creator: the Multiverse Theory
DISCOVER: Physicists are Close To Uncovering the Fundamental Rules of Reality–Brian Greene’s hopes for the next 30 years of science
DISCOVER: The Man Who Plucks All the Strings—a Brian Greene Q&A
DISCOVER: String Theory in Two Minutes or Less, a reader video contest
80beats: Hawking Says God Not Needed to Kick-Start Big Bang; World Freaks Out