What contribution did Yang Zhenning make to China?

Yang Zhenning actively promoted cultural exchanges and mutual understanding between the Chinese and American peoples, and made important contributions to the establishment of diplomatic relations, personnel exchanges and scientific and technological cooperation between the two countries. He also promoted the establishment of the Institute of Mathematical Sciences of the Chinese University of Hong Kong, the Advanced Research Center of Tsinghua University, the Theoretical Physics Laboratory of Nankai University and the Advanced Academic Research Center of Sun Yat-sen University. At the same time, he has made epoch-making contributions in the fields of particle physics, statistical mechanics and condensed matter physics.

In 1950s, he cooperated with R.L. Mills and put forward the theory of non-Abelian gauge field. 1956, he proposed the law of parity non-conservation by Li Zhengdao's weak interaction. In the field of particle physics and statistical physics, a lot of pioneering work has been done, and Yang-Baxter equation has been put forward, which has opened up a new research direction of quantum integrable systems and many-body problems.

Extended data;

Academic achievements;

Statistical mechanics is one of the main research directions of Yang Zhenning. His characteristic in statistical mechanics is to strictly solve and analyze the general model rooted in physical reality, so as to grasp the essence and essence of the problem. From 65438 to 0952, Yang Zhenning and his collaborators published three important papers on phase transition. The first article is about the spontaneous magnetization of two-dimensional Ising model, which he independently completed the year before last.

This is the longest calculation that Yang Zhenning has ever done. Ising model is the most basic and important model in statistical mechanics, but its importance in theoretical physics was not widely recognized until 1960s. 1952, Yang Zhenning and Li Zhengdao completed and published two papers on phase transition theory.

The simultaneous publication of these two articles aroused Einstein's interest. In this paper, the analytic properties of giant partition function are studied by analytic continuation method. It is found that the distribution of its roots determines the state equation and phase transition properties, which eliminates people's doubts about different thermodynamic phases under the same interaction.

The climax of these two papers is the unit circle theorem in the second paper, which points out that the zero point of the giant partition function of the lattice gas model attracting interaction lies on the unit circle on the complex plane.

Reference source; Baidu Encyclopedia-Yang Zhenning