Today, 123 years ago, on August 28, 1902 (July 25, 1902 in the lunar calendar), Zhou Peiyuan, a theoretical physicist and fluid mechanist, was born. Zhou Peiyuan (1902-1993) was a famous fluid mechanist, theoretical physicist, educator and social activist. Member of the Communist Party of China. Academician of Chinese Academy of Sciences, one of the founders of modern mechanics and theoretical physics in China. He was born on August 28, 1902 in a scholarly family in Yixing County, Jiangsu Province (now Wuxi City, Jiangsu Province). His father, Zhou Wenbo, was a scholar in the Qing Dynasty. In 1924, he graduated from the higher degree of Tsinghua University. Because of his excellent grades, he was sent by Tsinghua University to the United States to continue his college courses and enter the second year of the Department of Mathematics and Physics of the University of Chicago. He received his bachelor's and master's degrees in the spring and summer of 1926, respectively. In 1927, he entered the California Institute of Technology to continue his graduate studies. He first studied with Bedman and then studied relativity with E. T. Bell. The following year, he received a doctor of science degree and the highest honor award. In the autumn of 1928, he went to the University of Leipzig in Germany, where he engaged in quantum mechanics research under the leadership of Professor W.K. Heisenberg. In 1929, he went to the Higher Technical School in Zurich, Switzerland, and engaged in quantum mechanics research under the leadership of Professor S. Pauli. In the same year, he returned to China and was hired as a professor in the Department of Physics of National Tsinghua University. He was only 27 years old. From 1936 to 1937, he went to the United States and engaged in theoretical physics research at the Institute of Advanced Studies in Princeton. During this period, he participated in the seminar on general relativity led by Professor Einstein himself, and engaged in the research of relativity, gravity and cosmology. From 1943 to 1946, he once again used his vacation to go to the United States. He first worked on turbulence theory at the California Institute of Technology, and then joined the Naval Military Experimental Station of the Wartime Scientific Research and Development Agency of the U.S. Defense Commission to engage in war science research on torpedoes launching into water. In July, 1946, he left his job and went to Europe to attend the 300th anniversary of Newton's birth and the Council of International Scientific Unions; He also participated in the 6th International Congress of Applied Mechanics held in France, and was elected as a director by this congress and the newly established International Union of Theoretical and Applied Mechanics after the congress. In April 1947, he returned to Peiping with his wife and three daughters, and continued to be a professor in Tsinghua University. After the founding of the People's Republic of China, he served as provost of Tsinghua University, vice president and president of Peking University, vice president of Chinese Academy of Sciences, chairman and honorary chairman of China Association for Science and Technology, vice president of World Association for Science and Technology, chairman of China Association for the Promotion of International Science and Technology, chairman of Chinese Mechanics Society, chairman and honorary chairman of Chinese Physical Society, honorary president of European and American Alumni Association, vice president of Chinese People's Institute of Foreign Affairs, chairman of Chinese People's Association for Peace and Disarmament. In 1980, he received an honorary doctorate in law from Princeton University, USA. In 1980 and 1985, he won the "Alumni with Outstanding Contribution" award of California Institute of Technology twice. On November 24th, 1993, he did morning exercises as usual, and went to his wife's room to talk again. He felt bad and wanted to lie down, so he never got up again.