Celebratio Mathematica

Shiing-Shen Chern

Autobiographical facts about Shiing-shen Chern

Shiing-shen Chern

I was born on Oc­to­ber 26, 1911 in Kash­ing, China, a pro­vin­cial town about one hun­dred miles south of Shang­hai. My fath­er was a law­yer and gov­ern­ment of­fi­cial and it was con­sidered cer­tain that I was go­ing to fol­low in the foot­steps. However, in the next 50 years China was destined to un­der­go mo­ment­ous changes, with the side res­ult that I was go­ing to im­mig­rate to a new coun­try and even­tu­ally to be­come a mem­ber of this great Academy.

In the edu­ca­tion of my child­hood a main char­ac­ter­ist­ic was the train­ing of mind and out­look of life ac­cord­ing to the teach­ings of Con­fucius. Much time was spent on Chinese clas­sics, which even now is my hobby. Phys­ic­al activ­it­ies were neg­lected. My in­clin­a­tion to­ward math­em­at­ics was mani­fest only to the ex­tent that I had no dif­fi­culty study­ing for my­self the lim­ited amount of ma­ter­i­als on math­em­at­ics then avail­able to me.

My fam­ily moved to Tientsin in North China and I en­rolled in 1926 as a fresh­man in the Col­lege of Sci­ence of Nankai Uni­versity. Lack­ing ex­per­i­ment­al skill and in­terest, math­em­at­ics be­came my only choice of field. The choice was made easy be­cause of the in­spir­ing teach­ing of my teach­er Pro­fess­or L. F. Chi­ang. Pro­fess­or Chi­ang was the first one in China to start a math­em­at­ic­al lib­rary, with sub­scrip­tions of cur­rent journ­als. I read with great en­thu­si­asm art­icles in School Sci­ence and Math­em­at­ics, Math­em­at­ic­al Gaz­ette, and in par­tic­u­lar Ham­burger Abhand­lun­gen. The lat­ter con­tained a series of art­icles en­titled “To­po­lo­gis­che Fra­gen der Dif­fer­en­tial-geo­met­rie”, some of which are ele­ment­ary in nature, which opened my eyes.

After my gradu­ation in 1930 from Nankai Uni­versity, I entered Tsinghua Uni­versity in Peiping, which was the only uni­versity at that time with a gradu­ate pro­gram. I was guided to work on pro­ject­ive dif­fer­en­tial geo­metry, without real­iz­ing that it was a dy­ing sub­ject. The field has many routine prob­lems and it was there that I made my first sci­entif­ic pub­lic­a­tion. I should say, however, that one of my pa­pers was bet­ter than routine and that it was based on my own idea. In any case it was ex­cit­ing enough for me to have my pa­per pub­lished in a for­eign journ­al and to be ad­dressed by the Ed­it­or as “Doc­tor”.

It was clear to me that I should study in a west­ern coun­try in or­der to do ser­i­ous work. Be­cause of the ex­penses in­volved I had to wait for the com­ple­tion of my gradu­ate stud­ies to be awar­ded a gov­ern­ment fel­low­ship. In 1932 Blasch­ke vis­ited China end I took notes of his lec­tures. This, to­geth­er with my early ac­quaint­ance with his work, made it im­per­at­ive for me to go to Ham­burg, when I was awar­ded in 1934 a gov­ern­ment fel­low­ship for stud­ies in a for­eign coun­try.

My stu­dent years in Ham­burg were happy and un­event­ful. Blasch­ke gave ex­cel­lent gen­er­al ad­vice, Artin gave the most beau­ti­ful lec­tures, and I had many thor­ough and pa­tient dis­cus­sions with Kähler. The gen­er­al at­mo­sphere was friendly and in­form­al, in spite of the Nazi activ­it­ies. I fin­ished my D.Sc. de­gree in 1936. The thes­is was an ap­plic­a­tion of the meth­od of the great French math­em­atician Elie Cartan to prob­lems of the Blasch­ke school. I was totally im­pressed by the pro­fund­ity and im­port­ance of Cartan’s works. So when my fel­low­ship was ex­ten­ded an­oth­er year, I went to Par­is. The year 1936–37 which I spent in Par­is was de­cis­ive on my sci­entif­ic de­vel­op­ment. Through per­son­al con­tact with Cartan, I had a bet­ter grasp and per­spect­ive of his works, which later played an es­sen­tial role in a large area of mod­ern math­em­at­ics.

I went back to China in the sum­mer of 1937, just at the time when war broke out between China and Ja­pan. In 1937–43 I was a Pro­fess­or at Tsinghua Uni­versity and I moved with the Uni­versity through vari­ous parts of free China, fol­low­ing the de­vel­op­ment of the war. In 1943 I was in­vited by the In­sti­tute for Ad­vanced Study in Prin­ceton to vis­it the U.S. Al­though activ­it­ies in Prin­ceton were re­stric­ted on ac­count of the war, the strong tra­di­tion in to­po­logy al­lowed me to com­bine it with my pre­vi­ous train­ing in dif­fer­en­tial geo­metry and Lie groups to make some es­sen­tial pro­gress in glob­al dif­fer­en­tial geo­metry. The works done in this peri­od are among the most im­port­ant that I have done.

After the end of the war I re­turned to China in 1946. The Chinese gov­ern­ment just moved back to Nank­ing after the con­clu­sion of armistice with Ja­pan. I was asked to or­gan­ize a newly foun­ded In­sti­tute of Math­em­at­ics of the Aca­demia Sin­ica. In the brief peri­od of 1946/48 the In­sti­tute played a role in the train­ing of a num­ber of young Chinese to­po­lo­gists and geo­met­ers, some of whom are now act­ive in this field. Com­mun­ist ad­vance to­ward Nank­ing and the ul­ti­mate col­lapse of the gov­ern­ment made the con­tinu­ation of my work im­possible and I was in­vited by the In­sti­tute for Ad­vanced Study in Janu­ary of 1949. In the sum­mer of the same year I was ap­poin­ted a pro­fess­or of math­em­at­ics at the Uni­versity of Chica­go, where I re­mained till 1960. From 1960 I am a pro­fess­or of math­em­at­ics at the Uni­versity of Cali­for­nia in Berke­ley.

I have lec­tured ex­tens­ively in uni­versit­ies in Amer­ica, Europe, and the Ori­ent. I was in­vited to give ad­dresses in sev­er­al in­ter­na­tion­al con­fer­ences, in par­tic­u­lar the In­ter­na­tion­al Math­em­at­ic­al Con­gress of 1950 (Cam­bridge, USA) and of 1958 (Ed­in­burgh, Scot­land). In 1960 I was the Col­loqui­um Lec­turer of the Amer­ic­an Math­em­at­ic­al So­ci­ety. I have served as Ed­it­or of sev­er­al math­em­at­ic­al journ­als, in­clud­ing the Pro­ceed­ings of the AMS and the Trans­ac­tions of the AMS. I have been an as­so­ci­ate ed­it­or of many oth­er journ­als. I am a mem­ber of the Aca­demia Sin­ica (1948) and an hon­or­ary mem­ber of the In­di­an Math­em­at­ic­al So­ci­ety (1950).

I was nat­ur­al­ized a cit­izen on April 4, 1961. Three weeks later I was elec­ted a mem­ber of the Academy. In this re­gard I am fully con­scious of the es­teem and ap­pre­ci­ation that my ad­op­ted coun­try and my col­leagues hold for me.