THE UNIVERSE IN YOUR HAND

Galfard (co-author, with Stephen and Lucy Hawking: George's Secret Key to the Universe, 2007) takes readers on a number of imaginary trips through the universe to help them visualize the strangeness and beauty of our mysterious universe.

As a graduate student in theoretical physics at Cambridge University, the author worked on black holes under the supervision of Stephen Hawking. Since graduation, he has devoted himself to using imagery to popularize complex physics and cosmology for popular audiences lacking a background in advanced mathematics. “Picture yourself,” he writes, “on a faraway volcanic island on a warm, cloudless summer night” floating through the emptiness of outer space 5 billion years from now. It’s a time and place that allows you to witness the death of the sun and the end of our world. Following this jumping-off point, Galfard introduces the place of our galaxy in the larger universe of galaxies as far as 10 billion light-years from Earth. This leads him to a discussion of the expansion of the universe over time and the relative position of the Earth and three fundamental cosmological principles: “the laws of nature whatever they may be—are the same everywhere”; “there is no preferred position anywhere whatsoever; for a given observer, wherever located”; faraway galaxies will always appear to be moving away. In another imaginary trip, the author illustrates the effects of special relativity. To grasp the strangeness of quantum physics, readers must imagine shrinking to the size of an atom. In this imaginative and comprehensive survey of major scientific discoveries of the 20th and 21st centuries, the author also includes a discussion of how proponents of string theory are attempting to “unify all the known forces of nature into just one force (and therefore one theory).”

A useful book for readers to visualize the complex ideas of modern physics, best read as an accompaniment to a more rigorous treatment of the subjects covered.