Studying abroad is to return to serve the country, he returned to China to do "what the country needs" | Time Letter

Science has no borders, but scientists have a motherland. At the beginning of the founding of New China, batches of overseas students gave up the superior living and working conditions abroad, and embarked on the road back to China after going through many hardships, just to revitalize China.

Zheng Zhemin (first from left) on a summer outing during his study abroad

In 1948, Zheng Zhemin went to study at California Institute of Technology in the United States, where he studied under Qian Xuesen and made a name for himself in mechanics research. In Zheng Zhemin's view, "the purpose of studying abroad is to return to serve the country, and I have never had any other thoughts."

On February 17, 1951, Zheng Zhemin wrote to his father Zheng Zhangfei:

On December 4, 1951, I passed the general knowledge oral examination. Six professors took turns to ask questions. I hope to finish the thesis in early June. I teach applied mathematics to fifth graders, so I have little free time. I will prepare to return to China as soon as possible. It is our responsibility to participate in the construction. There is still a lot to learn abroad, especially the enrichment of practical experience. However, returning to China is also an opportunity to learn. In the same amount of time, I believe that I will get more in China than here.

Letter from Zheng Zhemin to his father

The cover of a letter written by Zheng Zhemin to his father

In June 1952, after obtaining his doctorate, Zheng Zhemin immediately applied to return to China, but he was detained by the local immigration bureau and his passport was confiscated. After being bailed out by a friend, Zheng Zhemin immediately sued to leave the country. Although he won the case, the US government banned him from leaving the United States on the grounds that it was "not conducive to American interests."

It was not until after the Geneva Conference in 1954 that the U.S. Immigration Bureau lifted the restriction on a group of international students from leaving the country. Zheng Zhemin took a boat from New York in September and traveled to France, Switzerland, Singapore and Hong Kong, which took nearly half a year. He returned to his homeland in February of the following year after being away for six and a half years.

In February 1955, Zheng Zhemin (center) was photographed passing through Hong Kong on his way back to China

On the eve of Zheng Zhemin's return to China, Qian Xuesen once said to him: "We should do whatever the country needs." Zheng Zhemin remembered this sentence all his life and followed it all his life.

As an initial participant in the establishment of the Institute of Mechanics of the Chinese Academy of Sciences, Zheng Zhemin pioneered the discipline of "explosion mechanics" from scratch. Over the past few decades, "explosion mechanics" has solved many engineering problems and made an indelible contribution to my country's national defense and national economic development.

Zheng Zhemin (1924-2021)

Explosion Mechanics Expert

Academician of the Chinese Academy of Sciences

Academician of the Chinese Academy of Engineering

This column would like to thank the "Old Scientists Academic Growth Data Collection Project" for providing material support