Book Review: The 4 Percent Universe: Dark Matter, Dark Energy and the Race to Discover the Rest of Reality by Richard Panek

Twelve years ago, astronomers studying distant, exploding stars made a discovery that irrevocably altered humankind’s view of the universe. Most scientists had assumed that the universe’s expansion, which began during the Big Bang, had steadily slowed due to gravity. But the astronomers found that the cosmos was instead expanding faster; gravity had somehow transformed from a cosmic pull into a cosmic push.

The unseen stuff supplying this mysterious push has come to be called dark energy. Together, dark energy and dark matter, the invisible material that scientists say must exist to explain galaxy formation, make up most of the universe. Left over is a measly 4 percent to form everything else, like people and planets.

In his aptly titled book, science writer Panek writes eloquently about the mind-bending search for meaning in a universe dominated by stuff no one can see. Panek weaves together concepts from particle physics, relativity, quantum mechanics and cosmology with personal portraits of astronomers. Vera Rubin, a pioneer in gathering evidence of dark matter, and various players in the discovery of dark energy are seen as they alternately scratch their heads at astonishing findings and bitterly squabble over who was first to announce them.

In the end, the legacy of dark-energy theory “wouldn’t be personal acrimony,” Panek writes. “It would be the revolution in thought that dark energy mandated. Almost certainly this revolution would require the long-awaited union of general relativity and quantum theory. It might involve modifying Einstein’s equations. It could feature parallel, intersecting or a virtually infinite ensemble of universes.…What greater legacy could a scientist leave a universe?”

Houghton Mifflin Harcourt, 2011, 320 p., $26.