Mr. Zhang Li, 95, is the oldest teacher at Tsinghua University. Hu Jiazhong, 32, ushered in his first year teaching in Tsinghua Garden. This spring, Tsinghua University launched a large-scale, real-time, interactive, remote, and decentralized online classroom teaching for the first time. The two, who were teachers and students, jointly launched the "Front Topics in Quantum Mechanics". On February 20, they made their online cloud classroom debut.
Online "refurbishment" of traditional courses
At 9:20 am, there is still a short time before class, Zhang Li and Hu Jiazhong are ready to debug, set ringtones, and be ready to go!
"Jia Zhong is a very good experimental physicist. With him, this class broke through the research level of theoretical physics, introduced the perspective of experimental physics, and became more cutting-edge and richer. This is very worth looking forward to! We 'Partners', the challenge is unlimited! "Zhang Li said. The topic "Selected Topics in Frontiers of Quantum Mechanics" started in 1998, and Zhang Li talked for 22 years. As a graduate professional course, many senior undergraduates take this course every year.
Hu Jiazhong was sitting in the classroom of Tsinghua Garden ten years ago and he was fascinated and longed for the wonderful world of quantum physics. Ten years later, he was sitting next to Mr. Zhang and taking the same class, learning everything from master to master .
"Mr. Zhang's class is not like a general basic course. Everything can be found in books. Many of Mr. Zhang's lessons are cutting-edge, and they may not be clearly written in the book. They need to be continuously studied and studied. This made us feel very at that time. There is gain. "Hu Jiazhong said.
Start student perspective "listening" network
"The biggest challenge I may face is my age, which makes my thinking less agile than when I was young!" Zhang Li's laughter was loud and full of confidence. It was hard to believe that he was already over ninety years old.
"This method of class is simply too good, especially for students!" Zhang Li said, students in traditional classrooms "do not dare" to ask questions, while in online classrooms, students ask questions at any time through WeChat groups, and teachers answer in time. All the issues are clear at a glance, and they can communicate with each other to promote independent thinking. After several trial lectures, Zhang Li has fully adapted to the online teaching method. They have a good way to cooperate with each other. When Zhang Li was giving a lecture, Hu Jiazhong used another computer to open Rain Class, and chose "Student Perspective" to "monitor" the network sound quality at all times, and opened the mobile phone WeChat group to keep an eye on The questions raised by the students in the group are fully controlled, grasped at all times, and responded in time.
At 9:50, as the bell rang, Zhang Li and Hu Jiazhong immediately engaged in intense teaching.
"Good morning, classmates! Today we are going to talk about the very important content of the quantum effect-superconductivity. Let us first understand the BCS wave function." Zhang Li opened the PPT page in English. 95-year-old Zhang Li leaned freely on the back of the chair, the handbook at hand was placed at the table, and there was no other written material. But he didn't actually look at the lecture notes. Sometimes he looked at the computer, sometimes he simply looked out the window. The extensions and stories of the slightly difficult superconducting theory flowed like a spring.
Motivation comes from years of exercise
In order to talk about the "frontier", Zhang Li has been racing against time. He once shared his daily schedule: at five in the morning, he got up to read the literature. When not in class, I went to the Office of Tsinghua Advanced Institute to continue reading the literature, at least 8 hours a day, sometimes even on Saturday.
In the neat office, there are various academic journals in English, "Science" and "Nature" magazines bound into volumes, the name and date are marked on the spine; there are neatly bound English documents on the desk; English documents occupy most of the desktop on the computer ... … The textbook “Front Frontiers in Quantum Mechanics” which he wrote to support the course has been updated to the third edition ... Zhang Li is also a frequent visitor to various lectures of the Graduate School of Research. He is always sitting in the first row. To impress young students. Han Tonghang, a student of the Department of Physics at Tsinghua University, remembers that he first saw Mr. Zhang during the lecture. "He basically listens to every lecture and often asks questions."
Master, is the best role model
After ninety years, why is there such a great spirit? Zhang Li attributes this to exercise. Since 1977, Zhang Li has started running in the morning. This habit has persisted until the age of 90. "After running, some academic problems have not been thought out and I have ideas." After that, on the advice of the doctor, Zhang Lichen practiced and changed. To walk quickly around the auditorium. People often ask, how long do I have to teach for more than 70 years? Zhang Li said, as long as I remembered that I had to go to class, my spirit was completely different. "If one day, my brain is dead, I ca n’t understand, I do n’t understand, then I surrender. But before that, I will never give up.