How does J. Robert Oppenheimer symbolize the concepts of sacrifice and death in this book?

Oppenheimer's story is not as well known as Truman's or MacArthur's, but his scientific know-how is actually more important to the development of the bomb. As much as, his knowledge, though, Oppenheimer's work ethic and eccentricity appear to contribute to his success in carrying out the Trinity test. What are the signs of the sacrifice his work schedule demands? How do his unusual beliefs contribute to his work? Is he a sympathetic figure?