On this day, 48 years ago, on November 30, 1977 (October 20, 1977, the lunar calendar), Wu Youxun, a pioneer of modern physics in China, passed away. Wu Youxun (February 26, 1897-November 30, 1977) was a physicist, educator, and pioneer of modern physics in China. The word Zhengzhi was born in Gao 'an, Jiangxi Province. Wu Youxun fully verified the Compton effect and developed the theory. The Compton effect, also known as the "Compton-Wu Youxun effect", is an important foundational discovery of quantum mechanics. After the Compton effect was verified, Compton won the 1927 Nobel Prize in Physics for this theoretical achievement. Although Wu Youxun was not awarded the Nobel Prize for his contribution to the X-ray scattering effect and quantum mechanics, he is recognized as the first Chinese scientist to make significant contributions to modern science in the world. In terms of developing Compton scattering theory, Wu Youxun used precise experiments to solve the problem of the ratio of energy or intensity between the variable line and the constant line in the Compton scattering spectrum. In November 1925, the 135th session of the American Physical Society was held in Wu Youxun's laboratory. Among the papers read out and exchanged at the meeting, Wu Youxun's paper "Energy between Variable Lines and Invariable Lines in the Compton Effect" Distribution "ranked first. After returning to China, Wu Youxun established China's first modern physics research laboratory, pioneered physics research in China, and was known as the "founder" of physics research in China. Wu Youxun has been engaged in education for a long time and has trained a large number of famous scientists such as Wang Ganchang, Qian Sanqiang, Qian Weichang, Deng Jiaxian, Yang Zhenning, Li Zhengdao, and Feng Duan. In 1935, he was elected as an academician by the German Academy of Natural Sciences and was the first China to be awarded the title of academician by a Western country. Photo: Old photo of Wu Youxun. Comment: Great scientist of China