He has written two books: Lonely Hearts of the Cosmos, about scientists and their quest to understand the universe, and Einstein in Love, dealing with Albert Einstein's youth and the controversy surrounding the degree to which Einstein's first wife, Mileva Marić, contributed to the theory of relativity. He joined the staff of The New York Times in 1998 as deputy science editor, then switched to full-time writing. In 2014 he was a finalist for the Pulitzer Prize for Explanatory Reporting.
Lonely Hearts of the Cosmos: The Scientific Quest for the Secret of the Universe, Harper-Collins (1991), ISBN 0-06-015964-2 & ISBN 0-330-29585-3 (finalist, Nation Book Critics Circle Award for non-fiction). Second edition (with new afterword), Back Bay, 1999.