Leon N. Cooper, a Nobel-winning physicist who helped unlock the secret of superconductivity and who did pioneering work in understanding how memory and the brain work, died on Oct. 23 at his home in Providence, RI. He was 94.

Some of the greatest physicists of thed 20th century, including Albert Einstein, Niels Bohr, Werner Heisenberg, Wolfgang Pauli and Richard Feynman, tried to explain how superconductivity works. Dr. Cooper helped crack the code with two colleagues at the University of Illinois — John Bardeen and J. Robert Schrieffer. Years later, Dr. Cooper recalled that if he had known how many eminent scientists had tried and failed to solve the concept of superconductivity, he probably would not have tried.

Dr. Cooper spent most of his career at Brown University, where he became interested in neuroscience and went to work on one of the central puzzles in the field: how people learn. Among the discoveries was how people learn to see.

According to Dr. Cooper’s daughters, when he was young, he told his father that he wanted to become a physicist because “there is no other way that I can know about everything.”