Margaret Harris reviews Reality Is Not What It Seems by Carlo Rovelli
Back in 2015, the surprise hit of the popular-science world was a slender volume with the English title Seven Brief Lessons on Physics. Written by the Italian-born theorist Carlo Rovelli, and intended as a basic introduction to post-Newtonian physics, the book’s Italian edition sold some 300,000 copies. Rovelli’s follow-up, Reality Is Not What It Seems, is longer and a bit more technical, and unlike its predecessor, it focuses on loop quantum gravity – Rovelli’s main research area and a topic seldom covered in general-audience publications.
The book begins conventionally, with the atomic theories of Democritus and other thinkers from the ancient Greek world, and then (rather regrettably) treats the ensuing 1.5 millennia as if nothing scientific happened whatsoever. After Democritus and Ptolemy, we jump from Copernicus, Kepler and Galileo to Newton, Faraday and Maxwell; and finally Einstein and a coterie of early 20th-century quantum revolutionaries.
Despite this standard-issue structure, the ideas of Democritus and other great scientists of the past are not mere starting points, but touchstones for all subsequent theories, and Rovelli refers back to them regularly throughout the book. His treatment of relativity, and particularly his claim that special relativity is “more difficult to digest than general relativity” (clearly, being a loop quantum gravity theorist does exciting things to one’s digestion), are also unusual. However, Rovelli has a gift for presenting complex ideas in a way that makes them seem intuitive, without diminishing their depth or lustre.
Physicists wishing to grasp the essentials of loop quantum gravity without tangling with its mathematics could not wish for a better guide in the book’s second half, when the subject matter passes from “what…we credibly know about the world, to what we don’t yet know but are trying to glimpse”.
- 2016 Allen Lane £16.99hb 272pp
