The next 15 years or so represented a productive and happy time for Einstein on both the personal and professional fronts. He simultaneously studied and taught at the Zurich polytechnical school, tutored for a while, became a Swiss citizen and in 1902 accepted a job as an examiner of patents at the Berne patent office; the position, in which he stayed for seven years, stimulated him intellectually and yet left him time for his own quantum-theory research, and it was a period he always looked back upon fondly. In 1903, he married Mileva Maric, with whom he went on to have two sons, Hans Albert and Eduard. During this time, Einstein earned his Ph.D. at the University of Zurich and began to publish the first of his significant papers. By 1912, a full professor at his old polytechnic, he was enjoying widespread acceptance of his theory of relativity. Membership at academies of science throughout Europe naturally soon followed, and his most famous honor, the 1921 Nobel Prize for physics, cemented his position as Europe's pre-eminent scientist. On the domestic side, however, he and Mileva had divorced in 1919; Einstein was immediately remarried to his cousin, Elsa Lowenthal, whose daughters he adopted. And Einstein had suffered his first debilitating bout of stomach ulcers, which forced him onto a detested bland diet for the rest of his life.

But true storm clouds were building. Einstein had been a vocal pacifist during World War One, and now, as the hand of fascism began to make itself felt, the Jewish genius and a devout Zionist knew that his days in Europe were numbered. As Germany slid into a Depression and Hitler leapfrogged to power, the Einsteins applied for visas to America. Seizing the moment, the Institute for Advanced Study in Princeton, New Jersey, offered him a life appointment. Einstein accepted and left Germany forever in 1933.

Einstein's residency at 112 Mercer Street and his tenure at the Institute provides the real-life setting of Einstein: Light to the Power of Two. Interestingly, the story of his relationship with a young girl who asked him to help her with her arithmetic--offering candy as a bribe--has become an oft-told tale with many variations, but such was the case. (The girl's name was Adelaide Delong.) Einstein always had a soft spot for children, whose innocence and wide-eyed fascination with life reminded him of his own early attempts to make sense of the world; he also empathized with children forced to endure the strictures of school, with all its rules and regulations. By contrast, to be sure, the behavior of the adult world frequently appalled him. In the early '30s, narrow-minded American organizations had tried to block his own entry into the U.S.--on the pretext that if he was anti-fascist he must, in turn, be a Communist--and it was with horror and disgust that he then watched his adopted country submit to the anti-intellectual madness of the McCarthy hearings, which swept up the likes of his friend and colleague, J. Robert Oppenheimer. A refugee himself, he was inordinately sensitive to oppressed minorities everywhere--and didn't have to look far to find a focus for his concerns on the eve of the American civil rights movement. (This preoccupation, and the real existence of Adelaide Delong, encouraged the film's producers and screenwriter to make their youthful protagonist an African-American child.) Last but not least, the militarization of science and the subordination of civil rights and human values to political considerations and so-called "national interest" distressed him without end.

Widowed in 1936, Einstein remained in Princeton when not traveling to speak at selected venues or reluctantly accept awards--knowing, and he was correct, that the world would beat a path to his door whenever it wanted his opinion. His faithful secretary, Helen Dukas, who assumed housekeeping duties after Elsa's death, did her best to guard his privacy. On April 18, 1955, Albert Einstein died at 112 Mercer Street. He was cremated and his ashes were spread at an undisclosed location. His 76-year-old brain was, as he requested, left to science.