Xiong Quanzhi’s career in the United States

Studying experience at Michigan State University

On the day before Christmas in 1945, Xiong Quanzhi left Chongqing. In addition to dropping a "small anchor" in Kunming, the plane Fly to Calcutta smoothly at night. I was very lucky. I only stayed for a month and boarded an American small cargo ship. The main mission of this ship is to repatriate American soldiers back home. There were also several female passengers on the ship, two of whom were family members of military personnel. The ship passed through the Mediterranean Sea and traveled for 30 days before arriving at New York Harbor on February 25, 1946.

Michigan State University Spring College will start classes in late March. Xiong Quanzhi took advantage of his free time before the start of school to stay in New York for two weeks, sightseeing around and visiting Professor P.A. Smith of Columbia University. Smith is the editor-in-chief of Bulletin of the American Mathematical Society and has published several articles by Xiong Quanzhi before, so the two of them wrote to each other several times. This time they met, they felt like old friends at first sight. Smith immediately invited Xiong Quanzhi to have lunch in the school cafeteria, and introduced several professors in the department, especially E. Kasner, a master of differential geometry. When Smith learned that Xiong Quanzhi wanted to study topology, he persuaded him to study for a degree at Columbia University and gave him a scholarship. Xiong Quanzhi felt that he was able to come to the United States entirely because of Grove's help, and he could not abandon his old benefactor as soon as a better opportunity arose; besides, there would be opportunities to study topology in the future. Xiong Quanzhi politely declined Smith's kindness and went to Michigan.

After Xiong Quanzhi arrived at Michigan State University in March 1946, Grove and Professor J.S. Frame, the head of the Department of Mathematics, took great care of him. The main subject for his doctoral degree is differential geometry, and the minor subject is statistics. Most of the other credits were transferred from Zhejiang University. His main difficulty was English, so he asked someone from the English Department to give him tutoring starting from pronunciation. After working hard day and night, he finally got results. In the summer semester of 1947, the Department of Mathematics opened a special small class for him to teach calculus. This lecture helped his English a lot. Since the fall, he has been teaching formal classes. By this time he had passed the preliminaries for a doctoral degree. In August 1948, he completed the credits and officially received his doctorate.

In June 1946, Mrs. Xiong Yu Wenqin took the American ship "President" from Shanghai to San Francisco, then transferred to Southeast New Town in Michigan, and arrived at Michigan State University in July. After taking a break for more than a month, I will take courses in the physics department. Later, because she gave birth to a daughter, she took half a year off before and after the birth, so she delayed getting her master's degree until March 1949.

Zhejiang University graduates studying at Michigan State University at that time also included Zhu Zuxiang and Zhao Mingqiang. In the autumn of 1946, President Zhu Kezhen came to the United States for a visit after attending a United Nations conference in Paris. He first went to Cambridge, Massachusetts. Xiong and Zhu, four Zhejiang University alumni, managed to arrange several speeches for Zhu Kezhen at their school. Zhu Kezhen stayed there for more than three days and had many long conversations with Xiong Quanzhi, which was very speculative. As the date for his return to China was approaching, Zhu Kezhen could not go elsewhere to meet other Zhejiang University alumni, so he went to Chicago and then to San Francisco before returning to China.

Zhu Kezhen gave Xiong Quanzhi a lot of help and encouragement at Zhejiang University. After meeting in Michigan this time, the friendship became even deeper. Zhu Kezhen often wrote to him, detailing various situations in the country. After liberation, Zhu Kezhen still sent letters. Once he asked Xiong Quanzhi to investigate for him Chinese scientific and technological personnel in the United States at that time. In the 1950s, he sent letters from China to encourage relatives and friends in the United States to return to serve in China, but Zhu Kezhen never urged Xiong Quanzhi to return to China in his letters. Because he knew that after Xiong Quanzhi achieved the goal he pursued academically, he would definitely return to China immediately. In 1951, Xiong Quanzhi received a text message from Zhu Kezhen at Harvard University, forwarded from Moscow, saying that he went to Poland to attend a scientific conference and then arrived in the Soviet Union. I have been abroad for three months and will fly back to Beijing soon. At the end of the letter, there was a question: "I sent you a letter in Beijing before going abroad. I wonder if you received it?" Xiong Quanzhi immediately wrote back and said that he had not received the previous letter. Due to the hostility between the Chinese and American governments, their communications have been interrupted since then. Xiong Quanzhi recalled: “After the restoration of diplomatic relations between China and the United States in 1972, he (Zhu Kezhen) asked people on his first visit to China about my situation. Later, I also wrote to him and told him that I was going to return to China for a visit, but Due to personal matters, the trip was delayed until 1975. He had passed away by then, so it was a great pity that I could not see him again." Later, Northwestern University near Chicago asked him for an interview. The head of the department there is Professor H.T. Davis. He said to Xiong Quanzhi: "Everyone in the department welcomes you.

No problem. Finally, it will be up to S., dean of the College of Arts and Sciences. E. Leland decided. Now I will take you to see him. "These words undoubtedly reminded Xiong Quanzhi to be careful when answering the dean's questions. It is said that the dean has great power in the school, probably more powerful than the principal.

As soon as they entered the dean's office, Xiong Quanzhi was stunned. Quanzhi found that the dean did not look like a very dignified administrator, but an easy-going, amiable scholar. At that time, the Korean War had begun, and China and the United States were at war. After the department director introduced him, the dean asked Xiong Quanzhi: "Are you a communist? " He felt that the dean was joking and had no other meaning, so he didn't mind. However, he thought that it would be too plain to answer simply "I am not". So he replied: "Sir, I am a math major. ． "The dean was shocked when he heard this. He thought this answer was neither humble nor arrogant, and was very extraordinary. He immediately said to the department chair: "Everything is fine. I have no more questions. "The dean of the department was also very happy. Xiong Quanzhi was hired as a part-time lecturer with an annual salary of US$3,600. He had to answer within a month whether to apply for the job. At that time, he had no chance to engage in research elsewhere. Only Witney from Harvard University Professor H. Whitney and Columbia University were particularly interested in him, but they would not know until August whether there would be funds to hire him. In the fall of 1950, he accepted the appointment from Northwestern University as scheduled. Unexpectedly, Witney. He and Smith both wrote letters inviting him to engage in research work there for two years, and the remuneration was the same as that of Northwestern University. In order to maintain his credibility, he negotiated an employment contract with Northwestern University, and finally adopted a compromise: Xiong Quanzhi would leave after teaching at Northwestern University for the fall semester. This gave the school a longer time to find a replacement. Since he had known Smith for a long time, he asked Smith to decide where it would be more advantageous for him to go to Northwestern University. Xiong Quanzhi accepted Smith's suggestion and decided to teach at Harvard University. After finishing the autumn semester, on Christmas Eve of 1950, with the help of his brother, they drove to Harvard University. From January 1951 to August 1952, Xiong Quanzhi worked as a researcher at Harvard University. Visited Witney. At that time, Witney was writing a book on geometric integral theory and was no longer engaged in topology work; N. Steenrod's book on fiber bundle topology had just been published. After reading it, Xiong Quanzhi had Ask Witney for advice. In addition, Xiong Quanzhi spent most of his time at the Massachusetts Institute of Technology listening to W. Hurewicz, G.W. Whitehead and W. Ambrose's lectures on topology and synchronization. At the end of March 1952, Witney told Xiong Quanzhi: "I have accepted a permanent appointment at Princeton's School of Advanced Study. I’m going there in August. You can still work at Harvard for another year. There is also O. Zariski, a master of geometry, who will take care of your work. If there are good teaching opportunities outside, you may also consider it. "Xiong Quanzhi was willing to stay at Harvard University. When he was about to find Zariski, Zarisky took the initiative to come to Xiong Quanzhi and said that Witney had asked him to take care of Xiong Quanzhi's work.

Xiong Quanzhi worked at Harvard University for one year and eight months, laying a good foundation in topology and overall geometry. Since Witney and Xiong Quanzhi talked in March 1952, Xiong Quanzhi was working and searching outside. Opportunities to teach. Professor G. Raynor, head of the Department of Mathematics at Lehigh University in Bethlehem, has known Xiong Quanzhi for several years and had a good impression, so he asked him to teach a three-course graduate course at Lehigh University. Xiong Quanzhi decided to go to Lehigh University in September 1952 because Bethlehem was close to Princeton and he could often attend lectures. He teaches at the university and trains graduate students. Since 1957, he has received grants from the U.S. Air Force and the National Science Foundation for 20 consecutive years. In 1958, his first graduate student received a doctorate. Since then, his number of students has gradually increased. At that time, there were 8 people. Offers from many schools came one after another. The best offer was a professorship with honors at Penn State University. However, the school was located in a remote location and was not accessible by super highways. It was very inconvenient, so he did not accept the offer. After learning about this, G. J. Christensen, the provost of Lehigh University, said to Xiong Quanzhi after discussing it: "The president and I are willing to do our best." Our competence

To keep you here. ”

Later, Xiong Quanzhi suggested to the provost to establish a “Journal of Differential Geometry” to promote in-depth research on differential geometry and enable Lehigh University to collaborate on research with other units. If this suggestion was made directly to the Department of Mathematics or The College of Arts and Sciences proposed that it would be met with jealousy. The provost told Xiong Quanzhi that the principal agreed with the proposal and asked them to talk to the principal. After they met with the principal, the principal asked Xiong: "What should I do?" In a magazine, the most important person is the editor. How can I approve your suggestion if I don't know your editor yet? Xiong replied: "If you don't authorize me, how can I ask for an editor?" "Both sides were reasonable. So a compromise was adopted: the principal authorized Xiong Quanzhi to hire an editor. If the editor was not competent, the principal could disapprove it. Later, the editors Xiong Quanzhi hired were all well-known authorities, and the principal immediately approved Xiong Quanzhi's suggestion and gave the After Xiong Quanzhi's letter to hire an editor was sent out, an editor called and said: "After I got your invitation letter, I checked all the differential geometry papers reviewed in "Mathematical Reviews" this year, and I couldn't find it. An interesting paper, so I doubt whether it is worth starting this journal? Xiong Quanzhi replied: "That is based on the old definition of differential geometry." He asked again: "What is your new definition?" Xiong Quanzhi replied: "All geometry papers related to differential equations, differential topology, algebraic topology, Lie groups, Lie algebras, etc. belong to differential geometry." He immediately said: "In this case, I will accept your invitation." "Journal of Differential Geometry" was founded in March 1967, and it has been nearly 30 years. It has provided important reference materials for the study of differential geometry. Now differential geometry has become a popular development direction, realizing his long-cherished wish more than 20 years ago. Xiong Quanzhi is the founder and editor-in-chief of the "Journal of Differential Geometry". The magazine has now become one of the most famous mathematics magazines in the world. Lehigh University first set up the "Xiong Quanzhi Mathematics Development Fund (C.C. Hsiung Fund for the Advancement of Mathematics)" with more than 500,000 US dollars (part of the profit). This fund will gradually increase every year. Lehigh University is one of the few universities in the country, and only two universities in the United States (the University of Illinois and the University of California, Berkeley) have similar mathematics funds. One of the uses of the "Xiong Fund" every year is to hold a seminar on geometry and mathematics at Lehigh University. World Mathematics Annual Conference on Topology.

Xiong Quanzhi was promoted quickly at Lehigh University, serving as an assistant professor from September 1952 to 1955, an associate professor from 1955 to 1960, and a concurrent post at the University of Wisconsin from 1959 to 1960. He was a visiting associate professor at the U.S. Army Mathematics Research Center and a full professor at Lehigh University from 1960. In the spring semester of 1962, he was also a visiting expert at the University of California, Berkeley. He retired in 1984 and served as a distinguished professor at the University of Granada in Spain from January to May 1986. Quanzhi has guided 20 graduate students to obtain doctoral degrees at Lehigh University. Most of them continue to teach in various universities, and several have served as department chairs, deans of research institutes, and provosts.