Almost weightless and able to pass through the densest materials with ease, neutrinos seem to defy the laws of nature. But these mysterious particles may hold the key to our deepest questions about the universe, says physicist Heinrich Pas. In The Perfect Wave, Pas serves as our fluent, deeply knowledgeable guide to a particle world that tests the boundaries of space, time, and human knowledge.

The existence of the neutrino was first proposed in 1930, but decades passed before one was detected. Pas animates the philosophical and scientific developments that led to and have...