Meet the 69-year-old professor who left retirement to help lead one of Google's most crucial projects

A year ago the University of California at Berkeley hosted a retirement celebration for David Patterson, who was hanging it up after a 40-year academic career in computer architecture. Patterson encored the event last May with a personal 16-minute history, chronicling his days as a wrestler in high school and college and a math major at UCLA, followed by a job at Hughes Aircraft and four decades at Berkeley. From writing two books with Stanford University's John Hennessy to chairing the Computing Research Association, Patterson told the audience that a key to his success was doing "one big thing at a time." Rather than hitting the beach after retirement, Patterson joined Google in July to work on an ambitious new chip that's designed to run at least 10 times faster than today's processors and is sophisticated enough to handle the intensive computations required for artificial intelligence. It's called the Tensor Processing Unit (TPU), and Patterson has emerged as one of the principal evangelists. He spoke to about 100 students and faculty members at the Berkeley campus on Wednesday, a few days shy of the anniversary of his retirement celebration.