One of Harvard's youngest Chinese full professors, Xi Yin, leaves OpenAI after only 5 months

On November 4, Zhi Dong Xi reported that yesterday, Yin Xi (Xi Yin), who came from the University of Science and Technology of China's Special Class for the Gifted Young and once served as one of the youngest Chinese full professors in Harvard University's history, announced on the social platform X that he was leaving OpenAI. He wrote: "I have decided to end this journey early and explore new directions."

In addition, he specifically thanked Alex Lupsasca (OpenAI research scientist) and Boris Alexeev (OpenAI researcher), saying the two helped him adapt to the first corporate job of his life, and thanked Dan Roberts (OpenAI scientist) for his ongoing support. Finally, he said: "I will always be cheering everyone on!"

At the end of May this year, people familiar with the matter spread the news that Yin Xi had joined OpenAI, and one day before that, another Chinese scholar, Weijie Su, had also officially announced joining the company.

During his time at OpenAI, Yin Xi did not stop physics research, but continued to explore the intersection of AI and theoretical physics, participating in advancing AI-assisted research related to string theory and quantum field theory, and in October, in the capacity of "Harvard University/OpenAI," introduced related results at Kyoto University, including presenting a new numerical method for calculating high-genus string amplitudes and compressed approximations of the ground-state wave function of BFSS matrix theory.

At present, he has not yet announced his next career plans.

1. News of joining spread at the end of May, two Chinese scholars enter OpenAI together

Yin Xi's early educational experience attracted considerable attention. He was the youngest student in the University of Science and Technology of China's Special Class for the Gifted Young at the time. According to a September 16, 2015 report on the University of Science and Technology of China news website, in 1996, at just 12 years old, he entered the USTC Special Class for the Gifted Young with a score of 572.

In 2001, at 17, Yin Xi completed USTC's five-year undergraduate program, then went to Harvard University in the United States to pursue a doctorate in physics, obtaining his PhD in 2006. Two years later, he joined the Harvard Department of Physics faculty, serving successively as assistant professor and associate professor.

In September 2015, at 31, Yin Xi was promoted to full professor in the Harvard Department of Physics, becoming one of the youngest Chinese full professors in Harvard University's history.

▲Yin Xi's personal introduction page on the Harvard University official website, image source: Harvard University official website

After that, Yin Xi conducted research in theoretical physics for a long time, with research directions mainly involving string theory and quantum gravity. It was not until the end of May this year that his career trajectory showed a change, with news spreading that he had joined OpenAI.

On May 30, the X account @dinq_me posted that Yin Xi had left Harvard University and joined OpenAI. However, the news was not officially confirmed at the time by Yin Xi himself, Harvard University, or OpenAI.

One day before news spread that Yin Xi was joining OpenAI, another Chinese scholar, Weijie Su, also officially announced joining the company.

Weijie Su graduated in 2011 from the School of Mathematical Sciences at Peking University and obtained a doctorate in statistics from Stanford University in 2016. His research directions include statistical machine learning, high-dimensional statistical inference, large-scale multiple testing, optimization, and privacy-preserving data analysis.

On May 30, Weijie Su posted on the social platform X, announcing that he had joined OpenAI. He said he was currently on leave from the Wharton School of the University of Pennsylvania, had joined OpenAI to participate in AI model training, and was very happy to return to the San Francisco Bay Area after 10 years.

At the same time, Weijie Su also announced his promotion to full professor in the Department of Statistics and Data Science at Wharton. OpenAI co-founder and president Greg Brockman also left a comment in the comments section of his post welcoming him.

2. Academic talent crosses over into OpenAI, leaves after only half a year

Yin Xi has long studied string theory and quantum gravity, and his research directions also involve fields such as black holes and conformal field theory.

According to materials on the University of Science and Technology of China official website, after Yin Xi obtained his doctorate in physics from Harvard University in 2006, he continued postdoctoral research at Harvard, and from 2008 served successively as assistant professor and associate professor in the Harvard Department of Physics, and was promoted to full professor in 2015.

In 2017, Yin Xi and Simone Giombi jointly won the Breakthrough Prize in Physics New Horizons award; the awarded research involved higher-spin gravity and its holographic connection with solvable field theories.

▲Yin Xi receives the 2017 New Horizons in Physics Prize, image source: Breakthrough Prize

During his time at OpenAI, Yin Xi participated in research at the intersection of AI and theoretical physics.

On October 16, in an academic report announced by the Institute for Basic Physics at Kyoto University, Japan, Yin Xi, in the capacity of "Harvard University/OpenAI," introduced multiple string theory and quantum field theory studies completed with AI assistance, involving numerical calculation of high-genus string amplitudes, approximation of the ground-state wave function of BFSS matrix theory, and Lean formal verification of mathematical theorems.

▲Yin Xi introduces academic report on string theory and quantum field theory research, image source: Institute for Basic Physics at Kyoto University

In addition, from October 19 to 23, 2026, the Kavli Institute for Theoretical Physics (KITP) at the University of California, Santa Barbara established the AI and theoretical physics intersection research program Intermediate-Scale AI for Physics, listing Yin Xi as one of six coordinators. The program aims to promote exchanges between theoretical physicists and frontier AI laboratories and explore how to further extend the capability progress AI models have achieved in mathematics to theoretical physics research.

In this departure announcement, Yin Xi called his experience joining OpenAI his first corporate job. He also said he hoped to end this experience early and explore new directions.

Conclusion: After leaving OpenAI, Yin Xi is still on the road forward

From entering the University of Science and Technology of China's Special Class for the Gifted Young at 12, to becoming a full professor at Harvard University at 31, and then crossing over to join OpenAI, every career choice of Yin Xi has attracted attention.

Now, Yin Xi has once again chosen to begin a new career journey.

Sources: Yin Xi, Harvard University official website, Weijie Su, University of Science and Technology of China news website, Breakthrough Prize, Institute for Basic Physics at Kyoto University, and KITP