Marvin D. Girardeau was a quantum physicist, and a faculty member in the Institute for Theoretical Science at the University of Oregon, where he was hired as a professor in 1963 and worked until his retirement in 2000, after which he became a research professor at the University of Arizona. He was a mathematical physicist with an unusual nonlinear career, which culminated in a remarkable impact in the ultracold atom physics community. One of Girardeau's achievements was to predict the existence of the Tonks–Girardeau gas in 1960. A Tonks–Girardeau gas was created in 2004, and its measured properties strikingly confirmed Girardeau's original predictions.