‘Collisions' Review: The Explosive Mind of Luis Alvarez

Wall Street Journal

11-07-2025

We tend to think of the great scientists—physicists especially—as high, cold heroes of disembodied thought, existing in their own spheres and unconcerned with the petty matters of this world. Einstein is the very model of the absent-minded professor, with his shock of white hair and basset-hound eyes and gnomic utterances on the doings of God, with whom he seemed to be on intimate terms.
And then there is Luis Alvarez (1911-88), whose range of interests, activities and achievements, as explored in Alec Nevala-Lee's 'Collisions: A Physicist's Journey From Hiroshima to the Death of the Dinosaurs,' is mind-boggling. Alvarez promoted the development of radar during World War II. He worked at Los Alamos on the building of the first atomic weapons and flew in a plane near Hiroshima to observe the effects of the detonation of the first bomb. He invented an X-ray method of searching for hidden chambers in the Pyramid of Khafre. He did important work on the construction of bigger and better particle accelerators. Oh, and he also put forward a counter-theory to the Warren Commission's verdict on the assassination of JFK.
Enough, you say, surely enough. However, in the last decade of his life Alvarez joined with his geologist son, Walter Alvarez, to propound the notion that the Cretaceous-Tertiary extinction, which saw off the dinosaurs, was caused by the collision between Earth and a very large meteorite. The theory, published in 1980 in a paper by the Alvarezes—co-authored with two nuclear chemists, Frank Asaro and Helen Michel—led to much controversy and many ill-tempered squabbles among geologists, some of whom were for it and many against. Then came the identification of an impact crater more than 100 miles wide on the Yucatán Peninsula, which settled the matter for all but a few unrelenting skeptics.
Alvarez, who had a Spanish grandfather, was an all-American boy right down to his fingertips—in his early years he was known as Sonny. He was born in San Francisco, and at the age of 15 moved with his family to Minnesota, where his father, a successful physician, took a position as a researcher at the Mayo Clinic.