Send this story Print this story

Adjust text size

Books: What an entangled web...
Bodega author makes quantum leap in book about 'spooky' science

by Cary James

THE AGE OF ENTANGLEMENT: WHEN QUANTUM PHYSICS WAS REBORN by Louisa Gilder. New York: Alfred A. Knopf, 2008. 445 pp. $27.50.

Louisa Gilder, who now lives in Bodega Bay, was a self-styled "lapsed physics major" who rekindled her interest in science while studying philosophy at Dartmouth. What delighted her, and prompted her to write The Age of Entanglement, was entanglement itself, the strange theory that says two quantum particles, once they have interacted, will remain interrelated no matter how far apart they move. This is Gilder's first book, and she has produced a stimulating introduction to quantum mechanics, told in a unique way through the dramatic form of human entanglement we call conversations.

Modern physics is divided into "classical" and "quantum" worlds. We live in the classical one, the world of Galileo, Newton and Einstein (at least his theories of relativity), a place we can, mostly, understand and predict. The quantum world, on the other hand, is that very small place inside the atom where everything must be described by mathematics, and even though you might understand the formulae you may not understand the world. Even Niels Bohr, who saw the atom as a nucleus surrounded by orbiting electrons, soon had to admit his idea was inaccurate, that it was futile to try to understand quantum events in our usual (classical) way.

Werner Heisenberg, famous for his uncertainty principle, was the first to use the term "entanglement." He also wrote that "Science rests on experiments, [but] science is rooted in conversations." In other words, the intellectual dialogues of scientists, played out in face-to-face conversations and arguments, are as important as the resulting theories.

Beginning with that idea of human interaction as a form of entanglement, Gilder re-creates a series of conversations that show us both the history and the excitement of scientific discovery. Using letters, papers and interviews, she brings to life the actual making of science, showing us conversations that took place in coffee shops and corridors, in labs and at universities, at social hours at science conferences and during long walks and even tram car journeys. Her dramatic reconstructions—especially in Europe in the 1920s, when the founders of quantum mechanics constantly met and talked and argued—make it clear that for all their intellectual struggles, this amazing collection of people—which included Einstein, Schrodinger, Bohr, Heisenberg and Pauli—were having the time of their lives.

Almost from the start quantum theory predicted entanglement. Two matching light photons, for example, will always display that same state, no matter how far apart they move. It's something like sets of twins who, even if separated at birth, often lead very similar lives; and it is so peculiar that in 1935 Einstein, unhappy with quantum entanglement, co-authored a paper in which he called it "spooky action-at-a-distance."

The rise of Nazi Germany cut short that series of conversations, and it was a quarter-century before science once again settled into some kind of normality. This second phase is Gilder's "rebirth," and she introduces yet another wonderful cast of characters, most notably John Bell, who built on Einstein's paper with the notion of "hidden variables" as a way to explain the "spooky" action of quantum particles. We now can create machines to test our understanding of quantum reality—where mass and distance are vanishingly small and energy levels are enormous—and over the years a series of experiments has proved this long-distance, instantaneous interrelationship of quantum particles actually happens. Bell spent much of his too-brief life at CERN, the European scientific establishment near Geneva, which has recently completed the Large Hadron Collider, the world's largest accelerator. The quantum story is far from over.

None of us, living our lives, have any idea what's coming tomorrow. Science, too, though it may seem like a string of self-evident formulae, is actually a half-blind and incremental advance toward a goal that can only be proven after it is discovered. Gilder's portrayal of science as conversation is dramatic and lively, and she's very good at describing both the excitement and frustration of scientific discovery. The Age of Entanglement is a brilliant and remarkable book—but be warned that even after reading it, you still may not understand quantum physics.