Heisenberg's life was one of controversy as well as triumph. Unwilling to leave his beloved homeland, Germany, he played a major role in conducting nuclear research during World War II.

Uncertainty was published to acclaim and two awards. Richard Rhodes (The Making of the Atom Bomb) called it "the definitive biography of a great and tragic physicist."

In Beyond Uncertainty, Cassidy offers a broadly accessible account of Heisenberg's contributions to quantum physics, and he explores previously unknown sources.