Exclusive | Why did Harvard top mathematician Liu Jun leave the US for China?

When it was officially announced in late August that statistician Liu Jun had left Harvard University and joined Tsinghua University in Beijing, speculation ran rampant. Was it political tension? Research funding cuts? A backlash against Chinese academics in the US? For Liu, the answer is simple – and deeply personal. It “has nothing to do with Trump”, he said in an email to the South China Morning Post, explaining that his decision was not out of political protest or professional disillusionment, but because of family and a lifelong bond with the Tsinghua campus where he was born. On September 7, the Post published the story of Liu Jun’s return to China, which spurred heated discussions on social media and online forums, especially in the academic world. Liu responded on September 9 to the Post’s email query. Liu did consider another prestigious American institution – the Wharton School – rather than a Chinese university. “I pretty much decided to move back to China by early 2024, at that time Wharton gave me a very generous offer and I almost accepted,” he wrote. Ultimately, he chose Tsinghua, mainly to take care of his elderly mother. “My mother was also ageing and really would like to have me around,” he said, adding that unfortunately she died at the end of this summer. Furthermore, there was “the draw of my hometown” – he was born on the Tsinghua University campus. “My decision was partly due to the family concern and partly due to my responsibility of taking the Centre of Statistical Science at Tsinghua to its next stage,” Liu wrote. “So this really has nothing to do with [US President Donald] Trump.” Born in 1963, Liu enrolled in a junior high school affiliated with Tsinghua University in 1976. There, he discovered his mathematical talent for the first time. In 1981, he was admitted to nearby Peking University to begin his mathematical career. At the Tsinghua welcoming ceremony on August 30, he said he was born and raised on the campus 60 years ago and had a deep and inseparable bond with the school. Asked if his decision to leave the US was related to the White House’s funding cuts for American universities, particularly Harvard, Liu said: “Not really, but felt fortunate to have made up my mind earlier.” Earlier this year, the Trump administration froze US$2.2 billion (15.6 billion yuan) in research funding for Harvard, along with around US$584 million for UCLA. This indirectly led to a halt of the financing for experiments and graduate student salaries for another top mathematician, Terence Tao. Regarding another very sensitive topic, Liu was also candid, admitting that he actively took part in the Chinese student activities around 1989. “Yes, it was about the Tiananmen Square event. As a young, enthusiastic student, we all participated in the demonstrations,” he wrote. In 1989, students held a massive demonstration in Tiananmen Square, and overseas student groups organised events in support of the cause. Chicago was then the centre of Chinese student activism in the United States. Liu was so actively involved in student activities in the United States that his mentor asked him if he wanted to be “a politician or a mathematician?” “I was never in a leadership role, more like finding a good excuse not to work in my office – which prompted my adviser’s soul-searching question,” Liu said in the email. “So this event has no impact on me at all in any sense in my later life. Also, nobody in China even had a question for me regarding such things.” He subsequently severed ties with the student movement organisation. He obtained a PhD in Statistics from the University of Chicago in 1991. That same year, he secured a position as an assistant professor at Harvard University. “My US green card application was processed and guaranteed by Harvard as I was a junior faculty there,” Lui wrote. In 1992, the United States Congress passed the Chinese Student Protection Act, which allowed many overseas students in the United States who took part in the Tiananmen movement to obtain green cards directly. According to reports, within the six years following the implementation of the act, the US government approved a total of 53,000 CSPA green cards. Although he is far removed from student movements, Liu has always been concerned about students – both those he has recruited and those he has not. He has guided more than 40 PhD students and over 30 post doctoral researchers. Most of them are now at top universities, while some are on Wall Street, at Google or Microsoft. “I am very grateful for my students; communicating with young people brings a great sense of achievement,” Liu Jun said in a 2012 interview with China Science Daily. “I hope that students will ask more questions, so that everyone can gain new inspiration and development from it. I quickly realised the importance of this approach. I also spend a lot of time with them, hoping they will succeed.” In the comments about his return, a former Chinese student reminisced about his interactions with him. “He is such a nice person. Two decades ago, I emailed him asking if his lab was accepting new students,” the former student said. “I was a poor student from a Tier 2 Chinese university, a nobody, and he still replied and offered a lot of help and guidance on applying to US graduate schools and scholarships. Kudos and respect!” In the past, Chinese university students regarded admission to top universities in the United States as a pathway to changing their destiny. In 2010, Liu Jun said at a Peking University alumni forum in New England that the United States was an immigrant country where a person rely on their abilities to make their American dreams come true. Fifteen years later, the situation has changed; the number of Chinese mainland students studying in the United States has fallen from a peak of 370,000 to 270,000. Even some who have settled in the United States are considering leaving, as another reader of the Post’s article commented on Reddit. “I worked at a university hospital until very recently. I am not the least bit surprised. I knew doctors who were leaving left and right,” one said.

.css-sioo19{color:#c79a00;}Exclusive | Why did Harvard top mathematician Liu Jun leave the US for China?

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}Professor’s decision to return to Tsinghua University amid rising tensions and US funding cuts had ‘nothing to do with Trump’

Exclusive | Why did Harvard top mathematician Liu Jun leave the US for China?

Professor’s decision to return to Tsinghua University amid rising tensions and US funding cuts had ‘nothing to do with Trump’