Photo of Chen Ning Yang

Chen Ning Yang

  • National Medal of Science
  • Physical Sciences

For his pathbreaking research in theoretical physics, which he has influenced for many years by his profound questions and deep mathematical insight. His ideas have had great impact not only on theoretical developments but also on experiments in elementary particles and condensed matter.

Nature is highly symmetric – from the structure of a snowflake to the Mickey Mouse-shaped water molecules it contains.rnrnAccording to the concept of parity, these objects, which mirror each other, must obey the same physical laws.rnrnChen Ning Yang, a Chinese-American theoretical physicist, helped find an exception to this rule, showing that parity is violated when elementary particles – subatomic components like quarks and leptons – begin to decay.rnrnThis concept is called “weak interaction,” a condition that spawns radioactive decay, playing a key role in the fission that powers nuclear plants and weapons.rnrnThe discovery won Yang a Nobel Prize in 1957.rnrn“I should like to say that I am as proud of my Chinese heritage and background as I am devoted to modern science, a part of human civilization of Western origin, to which I have dedicated and I shall continue to dedicate my work,” he said, accepting the honor.