Jennifer Ouellette in The New York Times:
Have you heard the joke about the elderly rabbi who tries to settle a bitter dispute between two men? The rabbi listens to one man’s case and pronounces him right. Then he hears the second man’s case, and concludes the second man is right. At this point his eavesdropping wife steps in and points out that both men can’t possibly be right. To which the rabbi replies, “And you are right as well!” That conundrum lies at the heart of two new books: Christophe Galfard’s “The Universe in Your Hand,” and Carlo Rovelli’s “Seven Brief Lessons on Physics.” Rovelli uses the case of the indecisive rabbi to illustrate the dilemma faced by theoretical physicists in the 21st century, except in this case what is under dispute are two competing “rule books” for reality: Einstein’s general theory of relativity, and quantum mechanics. Each functions perfectly well within its specific realm: Quantum mechanics governs the subatomic world of the very small, while general relativity describes how the world works at very large scales. But neither offers a complete description of how the world works.
Galfard is a protégé of Stephen Hawking’s, co-authoring a young adult book with Hawking and his daughter, Lucy, in 2007 (“George’s Secret Key to the Universe”). Those Y.A. roots show in “The Universe in Your Hand.” There’s a lot to be said in defense of plain, simple language, but in this case it proves a mixed bag. The earlier chapters read more like draft scripts for the television series “Cosmos,” covering very familiar ground (the sun, the moon, our solar system, stars and galaxies) without doing much to make the material seem fresh. More problematic is Galfard’s frequent use of the second person — no doubt to provide a stronger sense of immediacy for the reader — which wears thin rather quickly and adds a whiff of condescension to the overall tone. He also tends to repeat himself a great deal; for Galfard, if a point is worth making, it’s worth restating at least twice more. The book could easily be trimmed by a third by eliminating some of those redundancies.