Richard P. Feynman, a boy wonder who went on to win a Nobel prize and became a television folk hero during one of the nation's darker moments, died Monday night at the age of 69.
The Caltech physicist lost the final round in an eight-year battle with a rare form of cancer.
A spokesman for UCLA Medical Center said Feynman died from complications of recurrent abdominal cancer.
Although known throughout the world as a brilliant theoretical physicist, many of Feynman's greatest moments came in the classroom where he confronted generations of students with challenges of the intellect while regaling them with stories from his brash, unorthodox mind.
In the end, he seemed to devote almost as much energy to maintaining his image as a macho womanizer who loved a good laugh as to solving the mathematical mysteries which won him the Nobel prize for physics in 1965, an intrusion on his life style for which he said he never forgave the Royal Swedish Academy of Sciences.
Yet for all his achievements, Feynman would have escaped much of the public attention that came his way in the final year of his life had it not been for the role he played as a member of the presidential commission that investigated the explosion of the space shuttle Challenger.
As a scientist who had zealously shielded himself from committee assignments and other responsibilities that would have taken time he could otherwise have devoted to his love of physics, Feynman accepted the appointment reluctantly, and then went about the chore with gusto.
Seated before television cameras that beamed his image around the world, the old professor pulled off an impromptu experiment like a high school physics teacher, and in that single act cut through all the technical manuals and bureaucratic jawboning that threatened to conceal the real reason the Challenger exploded, killing seven people and plunging the nation into a period of despair.
He clamped a synthetic rubber O-ring from a model of the shuttle in an ordinary C-clamp, dropped the clamp into a glass of ice water, and then pulled it out and released the O-ring.
The "little experiment," as Feynman called it, showed that the resiliency of the O-ring was impeded by the cold temperature.
Weeks later, when the final report of the commission was presented to the President, it said essentially the same thing that Feynman had demonstrated in the type of presentation that had already made him a legend among his students.
Flair for Showmanship
In the end, he went out the way he had spent so much of his life, as a great teacher.
And it was that flair for showmanship, along with a healthy dose of humor and irreverence, that endeared him to the endless parade of potential physicists who passed through his classroom at Caltech, where he taught theoretical physics for 36 years. It was no fluke that mostly students were the ones to respond when a call went out for blood after his second operation for cancer in 1981. Within hours more than 100 pints had been donated.
Fellow Caltech physicist Robert Leighton said Feynman was almost too good of a teacher.
"He made things appear so simple in the classroom that you thought you understood it," Leighton said. "But when you got home that evening you found yourself wondering, 'How did he do that?' "
One of his former students, Albert R. Hibbs, now a senior scientist with the Jet Propulsion Laboratory, recalled what it was like to sit through a Feynman lecture.
"He would be standing in front of the hall smiling at us all as we came in, his fingers tapping out a complicated rhythm on the black top of the demonstration bench that crossed the front of the lecture hall," Hibbs wrote in the introduction to one of Feynman's books. "As latecomers took their seats, he picked up the chalk and began spinning it rapidly through his fingers in a manner of a professional gambler playing with a poker chip, still smiling happily as if at some secret joke.
"And then--still smiling--he talked to us about physics, his diagrams and equations helping us to share his understanding. It was no secret joke that brought the smile and the sparkle in his eye, it was physics. The joy of physics!"
Feynman is survived by his third wife, Gweneth Howarth, a son, Carl Richard, and a daughter Michelle Catherine. His second marriage ended in divorce, and his first wife died of tuberculosis while Feynman was working as a young physicist on the Manhattan Project, which gave birth to the nuclear age.
Asked once what he was most proud of in his life, Feynman paused for a long time and then answered:
"That I was able to love my first wife with as deep a love as I was able to."
Polishing an Image
A strange statement, perhaps, for a man who spent much of his adult life polishing the image of a skirt-chaser and a devil-may-care genius.