Meet Yang Zhenning, the Nobel Prize-winning physicist even President Xi Jinping wishes happy birthday to
- Yang Zhenning is about to turn 99 years old. Xi Jinping wished him a happy birthday
- The physicist won China’s first Nobel Prize and helped create an important maths problem
Not many people can expect to receive a personalised flower basket from one of the most powerful people in the world, but for Nobel laureate physicist Yang Zhenning, a happy birthday greeting from Chinese President Xi Jinping comes with the territory.
1957 Nobel Prize in Physics
Yang and his colleague Li Zhengdao were the first Chinese winners of the Nobel Prize in 1957 for their work in particle physics.
Specifically, they were at the forefront of disproving parity laws, which investigate the idea of whether nature can be right-handed or left-handed, according to the National Institute of Standards and Technology.
Before Li and Yang, scientists had long assumed that humanity’s preference for right-left-handedness was a function of our brain, not of nature. The assumption was that a mirror image of one object would perform identically to the original.
Li and Yang showed that, by reversing the magnetic field on cobalt-60, a radioactive atom, the original and mirror object had a different rate of radioactive decay. Hence, in some instances, the mirror does not perform identically to the original.
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A cosmologist answers questions about the expansion of the universe
This breakthrough was significant because it removed theoretical restrictions and led to further discoveries. At the time of the discovery, Yang was 33 years old and Li was 29.
The two scientists met in Kunming, the capital of Yunnan province in southwest China, in 1944. They had arrived in the city because it had become a base for intellectuals and students from across China to find safety during the Japanese occupation.
Li and Yang emigrated to the US after the war, where they pursued the research that eventually led to the 1957 Nobel Prize, given “for their penetrating investigation of the so-called parity laws which has led to important discoveries regarding the elementary particles.”
Li, now 94, taught at Columbia University until his retirement in 2012.
Yang-Mills Theory
While Yang’s status as a Nobel laureate landed him in history books, his work with the American physicist Robert Mills elevated him to the pantheon of mathematics.
Published in 1954, the Yang-Mills Theory is one of the most important problems in particle physics, in part because it has yet to be solved.
The theory found that quantum particles still have positive mass even though their classical waves (disturbances that transport energy) are travelling at the speed of light. It is called the “mass gap”, and experimentation has proven it accurate, but the maths problem itself has never been solved.
In 2000, the Post reported that solving the Yang-Mills Theory would probably require the discovery of new concepts in mathematics or physics.
Best of the rest
Yang spent much of his life investigating statistical mechanics, which tries to look at the behaviour of microscopic objects to explain how the macroscopic universe works.
He won a handful of top prizes in science, such as the National Medal of Science, which the US president personally presents. He was also named one of the “Ten Outstanding Young Americans” in 1957, a prize that extended beyond science.
In 1963, Princeton University published his textbook titled Elementary Particles. In 1965, he began working at Stony Brook University, where he would eventually see his name adorn a dormitory named C.N. Yang Hall.
He revisited China for the first time in 1971 after the thaw in relations between Beijing and Washington. In the decades since, he has worked closely in both countries and was a key figure in helping China rebuild its physics research infrastructure after the Cultural Revolution.
