JOHN W. FARRELL is an author and journalist working in Boston. His previous books include The Clock and the Camshaft: And Other Medieval Inventions We Still Can’t Live Without as well as The Day Without Yesterday: Lemaître, Einstein, and the Birth of Modern Cosmology. A graduate of Harvard College with a B.A. in English and American Literature, Farrell has written about science and history for The Wall Street Journal, Aeon, Commonweal, New Scientist, The Guardian, The Boston Globe, Salon, National Review, and Nautilus. His fiction has appeared in Dappled Things and DoubleThink, and his poetry in U.S. Catholic and Penwood Review.