Wang Yuan (April 15, 1930 – May 14, 2021) was a mathematician, academician of the Chinese Academy of Sciences, former director of the Institute of Mathematics of the Chinese Academy of Sciences, and chairman of the Chinese Mathematical Society. In 1952, after graduating from the Department of Mathematics of Zhejiang University, Wang Yuan worked in the Institute of Mathematics of the Chinese Academy of Sciences for a long time, making outstanding contributions in the fields of analytic number theory, algebraic number theory and application of number theory methods, and was one of the pioneers of the cause of mathematics in New China. Wang Yuan enjoys a high reputation in the mathematical circles at home and abroad, and has won the first prize of the National Natural Science Award, the Chen Jiageng Material Science Award, the He Liang He Li Award, and the Hua Luogeng Mathematics Award.
Wang Yuan is low-key, indifferent to fame and fortune, humble to others, "holding on to yuan virtue in his heart and turning into a god" (1), and it is this noble character that enables him to freely gallop in the mathematical world. I would like to use this short article to mourn Mr. Wang Yuan -- Mr. Wang Yuan, mr. Eons, the style will last forever!
Wang Yuan
There is no distraction
As a teenager, Wang Yuan's favorite subjects were mathematics and English.
He was fascinated by the precision of mathematical theory and the rigor of logic, especially the "hypothesis-proof-proof" model in planar geometry. Through the meticulous analysis of the topic, the gradual in-depth verification, and sometimes the addition of several "auxiliary lines" to complete the proof of the problem - this process of finding clues to solve the problem after repeated thinking has stimulated his endless interest. Whenever he tries to solve the problem, he can always bring excitement and satisfaction to the teenager.
After high school, Wang Yuan became fascinated by European and American literary and artistic films. From "Broken Blue Bridge", to "Battlefield Bells", "Marie Curie", "Spring Dawn", "The Prince's Revenge", "Gas Lamp", and some films based on Dickens's novels, he has been deeply impressed by the actor's superb acting skills and moving storyline.
In his spare time, Wang Yuan's interests are very extensive. In addition to watching novels, movies, and student performances, he was also keen on chess, bridge, swimming and other activities, and his lifelong achievements in calligraphy and painting laid the foundation at that time.
Paintings by Wang Yuan in high school
Geography, history, natural history, these homework to strengthen memory is not very attractive to Wang Yuan, he feels that he understands it by looking at the textbook, and is not willing to work harder and spend more time, so the comprehensive score is only moderate. In 1948, Wang Yuan was admitted to the Department of Mathematics of national Incess University (2). At this time, he began to regret that he did not concentrate all his energy on the study of schoolwork.
In 1949, most of the National Yingshi University was merged into Zhejiang University, so Wang Yuan entered the Department of Mathematics of Zhejiang University. In order to catch up with the progress of his studies, he gradually gave up all his hobbies and devoted himself to mathematics. Once, Hangzhou was screening "Gone with the Wind," a movie That Wang Yuan had wanted to see when he was in middle school, but he had no interest in it at all.
In 1952, Wang Yuan graduated from Zhejiang University with honors and was assigned to work at the Institute of Mathematics of the Chinese Academy of Sciences. Here, Wang Yuan is valued by Hua Luogeng and focuses on number theory under the guidance of Hua Luogeng.
Youth fame
The Goldbach conjecture was proposed by the German Goldbach in a 1742 letter to the great mathematician Euler: any even number greater than 2 is the sum of two prime numbers. Since it is the sum of two prime numbers , the problem can be shortened to " 1 + 1 " , which becomes a sign of the Goldbach conjecture. After the Goldbach conjecture was proposed, in the more than 160 years, despite the efforts of many outstanding mathematicians to prove this conjecture, no effective research methods were found, and no substantial progress was made.
It was not until the 20th century that the study of the Goldbach conjecture finally had a breakthrough.
In 1919, the Norwegian mathematician Brown proved that each sufficiently large even number is the sum of two positive integers, of which the number of prime factors of each integer does not exceed 9, which can be shortened to "9 + 9".
In 1924, the German mathematician Radaimaha proved "7+7".
In 1932, the British mathematician Esteman proved "6+6".
The former Soviet mathematician Bukhsitab proved "5+5" and "4+4" in 1938 and 1940, respectively.
These mathematicians, like athletes, sprint toward the ultimate goal of thoroughly proving the Goldbach conjecture, constantly setting world records.
Hua Luogeng believes that the Goldbach conjecture is related to all the important methods of analytic number theory, and learning from the Goldbach conjecture as the theme will greatly enhance the research height of analytic number theory. Therefore, in 1953, Hua Luogeng personally led two seminars: the "Introduction to Number Theory" seminar and the "Goldbach Conjecture" seminar.
Wang Yuan and Hua Luogeng (oil on canvas)
Wang Yuan participated in these two seminars, studied extremely intensely, and in addition to not being able to find Bukhsitab's articles, he quickly read all the required readings in the Goldbach Conjecture Seminar Plan. In 1955, the Polish mathematician Kulatowski visited Beijing, and he brought Hua Luogeng a single print of the papers of some Polish mathematicians, including Silpenski and Szynchler on the functions of number theory. After Reading the article, Wang Yuan thought that he could use the Brown Sieve method to improve Singel's results and write a text. As a result, Singel and Wang Yuan collaborated on two articles, which were published in Polish academic journals in 1956 and 1958.
In 1956, the state called for "marching towards science." The fact that young mathematicians trained by our country can cooperate with foreign mathematicians and publish articles abroad has been regarded as a major event, and many newspapers have reported on this matter, especially the "China Youth Daily" has introduced it in a full-page article, which has caused a sensation throughout the country. The 26-year-old Wang Yuan was set up as a typical example of his achievements in marching toward science and became a news figure across the country. But he knew soberly that this was only a small success by chance, and that the propaganda of the newspapers was not taken to heart.
"To be a big problem"
When Wang Yuan wrote the first article, the teacher Hua Luogeng was very happy; but when Wang Yuan made the second article, Hua Luogeng was very unhappy and said: "There must be speed, but also acceleration!" The so-called "speed" is to produce results; the so-called "acceleration" means that the quality of results must be continuously improved. He solemnly admonished Wang Yuan: "You have to do big problems. ”
Hua Luogeng's words caused Wang Yuan to think deeply.
Wang Yuan (right) and Hua Luogeng (left)
Wang Yuan began to focus on the Goldbach conjecture, a world-famous puzzle, trying to improve the existing results. He was desperate to find the only unread material in the Goldbach conjecture discussion class plan—Buchsitab's article. At this time, the library of the Chinese Academy of Sciences imported a batch of old Russian magazines, and Wang Yuan heard about it and immediately rushed to borrow it. The magazines had just arrived, had not yet been cataloged, and were piled on the floor of the library. At Wang Yuan's request, the librarian agreed to let him look at the library on the spot. So Wang Yuan spent the whole day copying two articles by Bukhsitab. Soon, he understood that the Buchhetab method is an identity, which can also be seen as a recursive formula for the sieve function, and each time it is recursed, the upper and lower bounds of the sieve function can be estimated to get some improvements.
At that time, Wang Yuan was already very familiar with the sieve technique, "the technique is already on the tip of the fingernail, as long as there is a little stimulation, it will blossom and bear fruit." He combined Selberg's method of screening with Thatbìsie's method and successfully proved "3+4" in 1956. In the same year, the Soviet mathematician A. Vinogradov proved "3+3". In 1957, Wang Yuan proved "2+3". This is the first time that Chinese scholars have stood at the forefront of this world-famous mathematical problem research field, and its results have been frequently cited in relevant literature at home and abroad, and have had an impact on subsequent research due to methodological innovations.
This research result became the most brilliant chapter in Wang Yuan's mathematical career, and also laid a solid foundation for Chinese mathematicians to continue to achieve results in the Goldbach conjecture.
Ride the world of mathematics
Subsequently, Wang Yuan turned his main direction of attack to the study of the application of number theory.
Wang Yuan cooperated with Hua Luogeng to apply the number theory method to multiple integral calculations, creating a numerical integration method known internationally as the "Hua-Wang method". After the English translation of their monograph "The Application of Number Theory in Numerical Analysis" was published by Springer Press, 14 mathematical magazines in more than ten countries, including Britain, Germany, Japan, and Austria, praised it as "a brilliant example in itself as far as the application of abstract mathematics is concerned."
In the 1980s, Wang Yuan delved into another frontier of pure mathematics— algebraic number theory. This period of work ended with the publication of the monograph "Diophantu Equations and Inequalities in the Field of Algebraic Numbers", and foreign experts commented that Wang Yuan's work in this field was "a valuable contribution to the literature related to the Hardy-Littlewood circle method".
After the 1980s, Wang Yuan cooperated with his colleague Fang Kaitai to apply the number theory method to mathematical statistics, creating a "uniform design method" that is widely used in industrial and agricultural production and national defense departments. This work has been valued by scientists such as Qian Xuesen and Zhu Guangya, and the monograph "Number Theory Methods in Statistics" has been praised by international peers as "a book with a high degree of ideological challenge" and "should be included in a valuable statistical library".
While concentrating on the study of mathematical theory, Wang Yuan also attaches great importance to the history of mathematical development, and his "Goldbach Conjecture" systematically sorts out the history of the Goldbach conjecture with original documents. His biographical work "Hua Luogeng" has a very large readership, and won the "Wu Dayu Science Popularization Book Award" Gold Signature Award, Springer Publishing House published the English translation version, is the only Chinese mathematician biography published by the publishing house so far.
Wang Yuan's academic achievements have earned him numerous awards and enjoyed an international reputation. He was elected a member (academician) of the Faculty of Chinese Academy of Sciences in 1980. He has won the first prize of the National Natural Science Award (1982), the He Liang He Li Award (1994), the Hua Luogeng Mathematics Award (1999), the Chen Jiageng Material Science Award (2000), the Wu Dayu Science Popularization Book Gold Award (2002), and the Second Prize of the National Natural Science Award (2008). Internationally, he is a consultant to the World Science Press, an editorial board member of the Federal Republic of Germany's Journal of Analysis, and an editorial board member of Springer's Graph Theory and Composition.
At 12:46 noon on May 14, 2021, the famous mathematician Academician Wang Yuan died in Beijing at the age of 91 due to ineffective medical treatment. Elders through the ages!
concentrate
(1) Quoted from "Huainanzi Yuandao".
(2) National Yingshi University was founded in 1928 to commemorate the martyr Chen Yingshi of Xinhai. By 1948, it was running a school in Jinhua, Zhejiang Province, with four colleges of arts and sciences, law, agriculture and engineering, and on August 25, 1949, Yingshi University was dissolved by the Jinhua Military Control Commission.
Text: Yang Jing, Associate Professor, Beijing Union University
Images of this article are provided by the author