·What is more important is not the direct role of mathematics, but that mathematics is an important aspect in cultivating and training people's abilities. The so-called innovation requires considering problems from the basic principles and original ideas, and then seeking breakthroughs. This is consistent with the ability requirements of mathematics for us.

·Yang Le and his lover Huang Qieyuan are classmates in the Department of Mathematics and Mechanics of Peking University. Huang Qieyuan came from a wealthy family. His grandfather was Huang Yanpei, and his father was Huang Wanli, a hydraulic scientist who cared about the country and the people all his life.

According to the Institute of Mathematics and Systems Sciences of the Chinese Academy of Sciences, Comrade Yang Le, an outstanding member of the Communist Party of China, an academician of the Chinese Academy of Sciences, a famous mathematician, and the first president of the Institute of Mathematics and Systems Sciences of the Chinese Academy of Sciences, died in October 2023 due to ineffective treatment for his illness. He died in Beijing at 14:34 on the 22nd at the age of 83.

Yang Le, a famous mathematician and the first dean of the Institute of Mathematics and Systems Sciences of the Chinese Academy of Sciences.

"Comrade Yang Le is a leader in the Chinese mathematics community and has made outstanding contributions to the reform and development of Chinese mathematics. He is a role model for an era, guiding and inspiring generations of young people to devote themselves to science."

Yang Le is mainly engaged in complex analysis research. "His outstanding achievements in value distribution theory were a representative work of Chinese mathematics that was world-renowned in that era."

In 1980, Yang Le was elected as a member (academician) of the Chinese Academy of Sciences, becoming the youngest academic member (academician) at that time.

Never leave the "number" in your life

According to the official website of the Institute of Mathematics and Systems Science, Chinese Academy of Sciences, over the past 30 years, Yang Le has achieved a series of important research results in function value distribution theory, argument distribution theory, normal families, etc.: 1. On meromorphic functions and their derivatives Accurate results were obtained in terms of the total deficit of , answering three questions raised by the famous expert D. Drasin, first revealing the countability of deficit functions; 2. In the theory of normal families of functions, fixed points and differential polynomials were studied The relationship between the value and regularity of The distribution law of Borel directions and the in-depth study of singular directions involving derivatives and heavy values were conducted. He also collaborated with British Professor WK Hayman to study a conjecture of the famous mathematician Littlewood. He obtained a universal and exact deficit relation for meromorphic functions involving heavy values.

Yang Le's research work in complex analysis has been widely cited by fellow scholars at home and abroad. He has been invited to give main or invited lectures at 20 international conferences, and has given academic lectures at more than 60 famous universities in the world. His English monograph is published by Springer-Verlag and Science Press. He has won many major awards such as the National Science Conference Award, the Second Prize of the National Natural Science Award, the Hua Luokeng Mathematics Award, the Tan Kah Kee Mathematical Sciences Award, and the Ho Leung Ho Lee Award.

What is the charm of mathematics that attracts him?

According to a 2012 report by People's Pictorial, Yang Le said that the charm of mathematics lies in truth and beauty. He believes that the "truth" of mathematics means that its pursuit of truth is very pure. For example, the famous Goldbach's conjecture is still a difficult problem in the world. Even if hundreds of millions of numbers can be verified by computers, as long as there is no strict proof in mathematical reasoning , it cannot be said that it is established. The "beauty" of mathematics is precisely contained in this rigorous logical reasoning. “Many times, the more high-quality and important the innovation, the simpler and more beautiful its expression is.”

Yang Le was born on November 10, 1939 in Nantong City, Jiangsu Province, on the edge of the Yangtze River. His father, Yang Jingyuan, had been the deputy manager of Nantong Tongming Electric Company for a long time and presided over the work. Yang Le had good academic performance since he was a child, and was later admitted to Nantong Middle School in Jiangsu Province. In high school, Yang Le was already a well-known math master in the school.

At the age of 17, in 1956, he was admitted to the Department of Mathematics and Mechanics of Peking University.

In the second half of college, due to changes in the social environment, Yang Le was sent to Puqi, Hubei. After work, he continued to study mathematics.

In 1962, Yang Le graduated from college with honors and was admitted to the Institute of Mathematics, Chinese Academy of Sciences. He became a close disciple of the mathematics master Professor Xiong Qinglai and a fellow student of Hua Luogeng.

Yang Le (left) and Hua Luogeng (right).

Yang Le recalled that Mr. Xiong Qinglai, who was nearly 70 years old, said to them: "I am old. Although I can't give you much specific help, I know the way." He followed Mr. Xiong and began to study the cutting-edge direction in the field of mathematics "function value". Distribution Theory”.

In a speech at Southeast University in 2010, Yang Le said, "I am from Jiangsu, and I feel very familiar returning to Nanjing. After finishing primary and secondary school in Jiangsu, I went to Peking University to study, and later to the Chinese Academy of Sciences for graduate school. The tutor is Mr. Xiong Qinglai. In the 1920s, Mr. Xiong came to Southeast University to establish the Department of Mathematics. During his tenure as professor and director of the Department of Mathematics, he trained many outstanding talents in mathematics, physics, and chemistry. The famous mathematician Yan Jici Sir is one of them."

According to an article published in the "Proceedings of the Chinese Academy of Sciences", under the guidance of Mr. Xiong, Yang Le completed the paper "Meromorphic Functions and Heavy Values of Function Combinations" in the first three months of graduate school, which was later published in "Journal of Mathematics" 》.

In 1964, 25-year-old Yang Le began to collaborate with Zhang Guanghou on the study of holomorphic and meromorphic function families, and achieved good results. An academic paper written in French was published in the journal "Science China" the following year. This research result happened to solve one of the "Several Problems in the Study of Function Theory" proposed by the famous British mathematician Hyman at an international mathematics conference in the same year, and attracted the attention of international colleagues. "But unfortunately, due to the lack of channels for scientific and technological exchange between our country and the international community at that time, we did not know about the issues raised by Hyman until many years later."

Since then, due to the influence of a specific historical period, the research work of the Institute of Mathematics, Chinese Academy of Sciences has been completely interrupted. Yang Le has completed his doctoral thesis, but failed to graduate normally. For four or five years, I had no chance to touch any mathematics books.

It was not until around 1971 that Yang Le gradually resumed his research work and could go to the library to check literature.

On February 26, 1977, the front page of "People's Daily" published an important report "Yang Le and Zhang Guanghou achieved important results in their research on function theory."

According to China Science News, they were established as intellectual models, and their names appeared in headlines on the front pages of major newspapers across the country and became famous throughout the country. "Becoming a mathematician like Yang Le" is a dream written down in the diaries of those born in the 1960s and 1970s.

From March 18 to 31, 1978, the "National Science Conference" was held. Yang Le not only participated in this event together with Hua Luogeng, Chen Jingrun, Zhang Guanghou and other colleagues from the Institute of Mathematics, Chinese Academy of Sciences, but also won the "National Science Conference Award". Chinese scientists are ushering in the “spring of science.”

Yang Le was elected as a member of the Chinese Academy of Sciences in 1980. In 1987, he became the director of the Institute of Mathematics, Chinese Academy of Sciences. In 1992, he became the chairman of the Chinese Mathematical Society. In 1996, he founded the Morningside Mathematics Center of the Chinese Academy of Sciences. In 1998, he became the first dean of the Institute of Mathematics and Systems Science, Chinese Academy of Sciences. He once served as vice chairman of the All-China Youth Federation, member of the National Committee of the Chinese People's Political Consultative Conference, and member of the Standing Committee of the China Association for Science and Technology.

According to a 2022 report by China Science News, Qiu Chengtong praised Yang Le as a "gentleman and a loyal elder." Yang Le and his lover Huang Qieyuan are classmates in the Department of Mathematics and Mechanics of Peking University.

Huang Qieyuan was born into an aristocratic family. His grandfather was Huang Yanpei , who left an important mark in modern Chinese history, and his father was Huang Wanli , a hydraulic scientist who cared about the country and the people throughout his life.

Huang Qieyuan, who has plenty of time after retiring from the Software Institute of the Chinese Academy of Sciences, is determined to find out "how to become a great scholar." Before his death in 2012, Huang Qieyuan wrote biographies of some people-Hu Xiansu, Meng Zhaoying, Chen Shengshen, Huang Wanli, Peng Huanwu, Wang Yuan, and Qiu Chengtong. The biographies are compiled into a book titled "The Great Scholar" . Yang Le wrote the preface and postscript affectionately, saying ""The Great Scholar" is the best memorial to Qie Yuan."

Talking about mathematics education

According to the official website of the Chinese Mathematical Society, Yang Le once recalled: "In my past contacts, even in a very poor environment, even a very poor family can still produce talents. Among China's top talents, there are leading professors in some disciplines. , many of them grew up under very poor economic conditions. The achievements of China's reform and opening up are obvious to all, and education is also developing. We must call for equal rights to education, otherwise it will be difficult for some talents to grow smoothly."

In his speech at Southeast University, Yang Le said that every scientific research is now inseparable from computers, but computers cannot replace mathematics. Although computers have been widely used in various subject areas, rigorous logical reasoning in mathematics cannot be replaced by computers. On the contrary, to use computers to conduct research work, we must establish mathematical models and select appropriate calculation methods and then perform calculations, compare the results of numerical calculations with our ideal accurate results, estimate errors, and measure the convergence speed, and these must Done by math. Therefore, computers are only a means for us to conduct scientific research and can never replace our logical reasoning. Therefore, as various disciplines increasingly use computers for research, the requirements for our mathematical accomplishment and ability are also increasing.

In August 2002, Yang Le and his wife (back row) took a photo with Hawking and his wife.

Yang Le said that what is more important is not the direct role of mathematics, but that mathematics is an important aspect in cultivating and training people's abilities. First of all, the quantitative relationships and spatial forms studied in mathematics can fully exercise our geometric intuition and spatial imagination abilities. Secondly, mathematics is a rigorous science that can exercise our rigorous logical reasoning ability. In addition, by doing math problems, we can exercise our analytical thinking, induction ability, proof ability and calculation ability, and all these abilities boil down to one point: innovation ability. China is currently in a stage of rapid development, and innovation capabilities are particularly emphasized. The so-called innovation requires considering problems from the basic principles and original ideas, and then seeking breakthroughs. This is consistent with the ability requirements of mathematics for us. If we can lay a good foundation in mathematics, then our abilities and qualities can be improved accordingly.

In an interview with China Teachers Daily, Yang Le said that mathematics has far-reaching significance in cultivating people's comprehensive abilities. To teach mathematics well, you must first understand the characteristics of mathematics. Mathematics is the most rigorous science. You must lay a solid foundation and proceed step by step. The key to mathematics education is to enable students to meet basic requirements and generate interest. For a long time, we have placed too much emphasis on high difficulty and high requirements, and assigned students a lot of homework. We need to liberate students from the heavy burden and allow them to learn easily, as long as they can meet the basic requirements. For students with excellent grades, it is more important for them to find reference books and learn to study on their own.

Yang Le has also put forward his own views on misconduct and academic ethics issues in today's academic world.

He believes that learning and scientific research are very noble undertakings, and we must pursue truth, goodness, and beauty. Without these, scholarship is impossible , so attention to academic style and integrity is crucial. Writing a paper is a pursuit of truth, while examinations are a means of examining the knowledge students have learned. Plagiarizing articles and cheating on exams are not only deception of knowledge, but also rebellion against the academic spirit. If you want to become high-end talents in various fields, you must not be hypocritical in your knowledge and life. Only in this way can you contribute to the development of the country, society, and profession.