Book Review: The Hidden Reality

Physicist Brian Greene’s latest popular science publication, The Hidden Reality, is a departure from his previous works in that domain. Subtitled Parallel Universes and the Deep Laws of the Cosmos, it sure sounds like something the deep-thinking writer of The Elegant Universe and Fabric of the Cosmos would write. But while his first two books serve as excellent primers on modern physics and modern cosmology, respectively, Greene isn’t interested in rehashing all that here.

Don’t get me wrong. For anyone looking to get a firm conceptual grasp on the deep physical laws which (apparently) govern the reality we live in, those titles are exactly where I’ll steer you. But there’s an untapped audience more interested in some of the implications of today’s cutting-edge physics than the details of the theories themselves.

To wit: parallel universes. The concept has spawned sub-genres in both science fiction and fantasy (alternate history and urban fantasy being perhaps the most prominent examples). More broadly speaking, most genre fiction imagines worlds perhaps highly disparate or only slightly tweaked from the one we know so intimately.

What makes The Hidden Reality a little more accessible than its written antecedents is its survey nature. Each chapter discusses a different theoretical multiverse, each implied by a different physical theory.

Our own three-dimensions of space and one of time might in fact be something akin to spots growing on the soap bubbles of a higher-dimensional brane, as described in string theory. We might exist in a virtual world, simulated on one of many computers in the “real” universe. We might find countless, infinitesimally-different versions of ourselves living in different quantum realities, endlessly splitting.

Greene wisely introduces the requisite scientific background only as needed, rather than spending the first third or half of the book slowly building up the edifices of quantum physics, general relativity, and inflationary cosmology.

It’s intriguing to imagine that one or several of these versions of a multiverse may actually exist, in some cases may be discoverable, and, depending on how they come about, may describe very different arrays of parallel realities. The idea of another version of you that is allergic to shrimp is interesting enough, but the concept of different universes with different fundamental constants, different origins and destinies, is fascinating in a different way.

I probably wouldn’t recommend this title to the decidedly casual reader. This is still Brian Greene, technically accurate, cogently argued, but intellectually demanding. But anyone with at least a passing interest in the real science behind other worlds should find The Hidden Reality illuminating.

(Vintage, 2011)

Reprinted with permission from The Sleeping Hedgehog
Copyright (2012) The Sleeping Hedgehog