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Xiao-Qi Sun (孙孝奇)

Student of Shoucheng

Hi, Everyone,

I am Xiao-Qi (孝奇) from a small town in China, I was Shoucheng's student until the end of 2018. I feel that, as the younger generation in China, I should share three pieces of memory that are very important for me and may help us to know the efforts that Shoucheng has put to my generation.

The first piece of memory is one series of seminars that Shoucheng organized for undergraduate students in Tsinghua university in 2012. It was called Science and Innovation. Shoucheng basically gave us a list of problems to study and present. In the 50th anniversary workshop of YITP, I heard Shoucheng talking about his days in Stony Brook and how he was impressed by the tastes behind the diverse problems that C. N. Yang chose for his class. I suddenly remembered his list for young students in 2012 at Tsinghua. At that time, the topic I chose was stable marriage problem and thanks to Shoucheng, I was married soon after I arrived at Stanford. Actually, two of the senior students who participated were Biao and Yingfei, who later also became Stanford graduate student and graduated from Stanford in 2017.

The second piece of memory is one wechat message that Shoucheng sent me when I was in Tsinghua university. I don’t remember for what reason we discussed about compressive sensing, an information technology. But I do remember that I wrote on the blackboard several linear algebra equations and Shoucheng was really unsatisfied. My mindset at the moment was that: "come on, it’s really simple linear algbebra." A few days later, we met again, and I started the old discussion again by asking Shoucheng: "suppose we have ten bags of coins, one of the bags is of fake coin. The good coin is 10 grams, the fake coin is 9 grams. If we have a scale, how many times we have to weigh the coins to figure out the wrong bag? "Shoucheng began to be very interested in this and enjoyed very much that every compressed sensing problem is essentially the same as this simple model. At very late night, he sent me a wechat message in Chinese, in English is, “to understand in your own way is the first step to innovation.” This moment made me feel proud of myself and motivated me a lot in later research.

The third piece of memory is at last year, October. I presented to him my latest work, mostly done when he was away from Stanford. Although this work can’t compare to his legendary works before, he was so happy for me. I think it was because, the main result can be summarized into a four-letter equation. We have only one letter to kill now. I will do better job, thanks, Shoucheng.