Overview of life
Ding Zhaozhong1936 65438+/KLOC-0 was born in ann arbor, Michigan, USA on October 27th, and went to primary schools in Chongqing, Nanjing and Qingdao successively. 1948 I went to Taiwan Province province with my parents and went to primary school in Taichung for another year. During the period of 1949, Ding Zhaozhong was admitted to Chenggong Middle School in Taipei, and then to Jianguo Middle School in Taiwan Province Province the following year, where he received strict education. He did well in math, physics and history. 1955 graduated from Jianguo middle school and was admitted to department of mechanical engineering, national cheng kung university. 1956 transferred to the university of Michigan, USA, and studied in the department of physics and mathematics successively. 1960 got the master's degree, 1962 got the doctor's degree in physics. 1963, he got a scholarship from Ford Foundation to work at CERN in Geneva, Switzerland. From 65438 to 0964, he worked at Columbia University. From 65438 to 0965, he became a lecturer at Columbia University in new york. Professor from Physics Department of Massachusetts Institute of Technology 1967. He is an academician of the American Academy of Sciences. His research interests include high-energy experimental particle physics, including quantum electrodynamics, unified theory of weak current, and quantum chromodynamics. The Mark Jay experimental group led by him has worked in several international experimental centers. Ding Zhaozhong's way of thinking and communication is extremely unique. The first communication with him makes people feel that his thinking is confused. But if you listen carefully, you will understand that his thinking is not chaotic, but that what he wants to say is too complicated to be expressed reasonably in words. I think everyone who has listened to his lecture has a deep understanding of this.
honour
Because of Ding Zhaozhong's contribution to physics, he was awarded the 1976 Nobel Prize in Physics, the American Lorenz Prize and the 1988 Tekasperry Prize in Science by the Italian government. He is an academician of the National Academy of Sciences, the American Academy of Arts, the Soviet Academy of Sciences, the Academia Sinica in China, and the Pakistani Academy of Sciences. He was awarded honorary doctorates by University of Michigan (1978), Chinese University of Hong Kong (1987), University of Bologna (1988) and Columbia University (1990). Honorary Professor of China Shanghai Jiaotong University and Beijing Normal University, Honorary President of Qufu Normal University and Rizhao Vocational and Technical College. 1977 won the Erin Gold Award of the American Society of Engineering Science, 1988 won the Jaguar Excellence Award of taormina, Italy, and the Brescia Science Gold Award of Italy. A few days ago, the 2005 World Physics Year was launched in Europe. He led 58 1 physicists from 43 first-class universities and research institutes in the United States, France, Germany and China to explore new substances in the universe on the world's strongest proton collider built in Geneva.
The importance of science
Ding Zhaozhong's academic thought is characterized by attaching great importance to experiments in scientific research. He believes that physics is developed on the basis of the close interaction between experiment and theory, and the basis of theoretical progress is that theory can explain the existing experimental facts and predict new phenomena that can be confirmed by experiments. When an experimental result in physics contradicts the theoretical prediction, a revolution will take place in physics and a new theory will emerge. According to the history of physics and personal experience of nearly a quarter century, he pointed out that many important experiments, such as the discovery of parity non-conservation and parity compound symmetry (CP) in the decay of K mesons, the discovery of J particles and the discovery of high-temperature superconductors, have opened up new research fields in physics, but these experimental discoveries were made without theoretical interest in advance. Another example is the basic discovery of particle physics made by high-energy accelerator experiments in recent years. Except for W particles and Z particles, almost all particles were not predicted when the accelerator was built. He stressed that no theory can refute the experimental results. On the contrary, if a theory does not conform to the facts observed in the experiment, then it cannot exist. His view of attaching importance to scientific experiments is of great guiding significance to scientific workers.
Major achievements
Found the J particle and won the Nobel Prize in Physics.
Since 1965, the experimental group led by Ding Zhaozhong has carried out a series of excellent experiments on quantum electrodynamics and vector mesons (ρ, φ, φ) at the electron synchrotron in Hamburg, Federal Republic of Germany (the beam energy is 7.5× 109eV), including the study of photogenerated vector mesons, the decay of vector mesons, and the experimental verification of vector-based models. Experiments also prove the correctness of quantum electrodynamics. In the summer of 1972, Ding Zhaozhong experimental group used the 3.3× 10 10eV proton accelerator of Brookhaven National Laboratory in the United States to search for long-lived hitting particles with the mass between (1.5 ~ 5.5 )× 109EV. 1974, they discovered a long-lived hit particle, whose mass is about three times that of protons (3. 1× 109eV). When publishing this discovery, Ding Zhaozhong named this new particle J, and the shapes of "J" and "D" are similar, meaning Ding Zhaozhong.
This is a particle discovered in China. At the same time, American B. richter also discovered this kind of particle and named it ψ particle. Later (1975), people called this kind of particle J/ψ particle. J/ψ particles have peculiar properties, and their life span is 5000 times longer than expected. This shows that it has a new internal structure, which cannot be explained by the known three-flavor quarks at that time, and it needs to be explained by introducing the fourth quark-charm quark. The discovery of J/ψ particles greatly promoted the development of particle physics. For this reason, Ding Zhaozhong and Li Xite both won the 1976 Nobel Prize in Physics. At that time, there was a misunderstanding in the press: J particle was considered to be named Ding particle. In fact, this is purely coincidental. Ding Zhaozhong's original intention was to use this particle to commemorate this important new discovery, which took them 10 years to explore the characteristics of electromagnetic current. In addition, it is customary to use J to represent electromagnetic current in physical literature, so Ding Zhaozhong named this new particle with the Latin letter "J".
quantum electrodynamics
Ding Zhaozhong's research focuses on experimental particle physics, quantum electrodynamics and the interaction between light and matter. Up to now, his major academic contributions are: (1) the discovery of anti-deuterium; (2) In the past 25 years, a series of experiments have been carried out to examine quantum electrodynamics, which show that electrons, muons and τ-ons are point particles with a radius less than 10- 16 cm; (3) the experiment of accurately studying vector mesons; (4) Studying the photogenerated vector mesons and confirming the similarity between photons and vector mesons; (5) the discovery of J particles; (6) Study on the generation of muon pairs; (7) Discovery of gluon injection; (8) Systematic study of gluon physics; (9) The accurate measurement of muon charge asymmetry shows the correctness of the standard electric weak model for the first time; (10) Within the framework of the standard model, it is confirmed that there are only three generations of neutrinos in the universe.
Enthusiastic training of high-energy physics talents
Starting from 198 1, Ding Zhaozhong organized and led an international cooperation group-L3 group, and prepared to carry out high-energy physics experiments on the high-energy electron-positron collider LEP which is expected to be built by the European Nuclear Center in 1988, and will analyze the energy of the center of mass system in1kloc-0/65438. At present, L3 Group has nearly 400 physicists from about 13 countries, including China. Ding Zhaozhong is keen on training high-energy physics talents in China, and often selects young scientists from China to work in the group he leads. He is an honorary professor of China University of Science and Technology and a member of the Academic Committee of Institute of High Energy Physics, Chinese Academy of Sciences.
Leading the experiment of "Alpha Magnetic Spectrometer" to explore antimatter
1On June 2, 998, at 6: 09 a.m. EDT, the space shuttle Discovery lifted off with the Alpha magnetic spectrometer Ding Zhaozhong developed by China and the United States.
"Running the experiment kicked off the first time that humans went to space to find antimatter and dark matter. Alpha magnetic spectrometer experiment is a large-scale international cooperative scientific experiment project. The experiment was led by Professor Ding Zhaozhong, including physicists and engineers from 37 research institutions in the United States, China, Italy, Switzerland, Germany, Finland and other countries and regions. There are no fewer than 200 scientists and engineers in China alone, whose purpose is to find antimatter and dark matter in space. Judging from the received 1% data, the data returned by the "Alpha Magnetic Spectrometer" running on the space shuttle this time is normal, and the expected antiprotons have appeared, but due to the small number, it cannot be said that antimatter has been found. Alpha magnetic spectrometer will return to the ground with the space shuttle on 12 this month. Next time, it will go into space again in 2002 and stay in space for 3-5 years. The Alpha Space Station will be established in the second half of this year, and the first batch of components will go into space for the first time on1998165438+1October 20th.
Edit this anecdote
Don't let go of any problem.
Ding Zhaozhong's ancestral home is Rizhao. Father Ding and mother Wang Juanying both teach in universities. During 1936, when Ding and his pregnant wife Wang Juanying went to the United States for an academic visit, Wang Juanying gave birth prematurely unexpectedly. The baby who came into this world early is Ding Zhaozhong. /kloc-in the winter of 0/948, Ding Zhaozhong began to receive formal education. Influenced by his family, he is meticulous and devoted to his studies. When he met a difficult problem, he looked through all the books and wouldn't give up until he got the answer. Once the physics teacher gave a thinking question. Many students find it difficult to give up and wait for the teacher to explain. Ding Zhaozhong is not like this. He wants to eat and walk, while other students go out for activities. Only he still lives in Ding Zhaozhong, Rizhao City.
Thinking hard about this problem, an hour passed, two hours passed ... finally, he thought of a solution to the problem. He immediately ran to the library to find information to verify whether his method was correct, and he was not satisfied until he confirmed that his method of solving problems was correct. He listens carefully in class, and whether he is sure of his answer or not, he is always the first to raise his hand to answer the teacher's question. When discussing problems with classmates after class, we often argue that we have a clear understanding. He spends most of his spare time in the library and seldom plays ball games and watches movies with his classmates. He believes that "the most wasted thing is time." Thanks to Ding Zhaozhong's efforts, he achieved excellent results in all subjects, especially in mathematics and physics, which laid a solid foundation for him to achieve his lifelong goal.
Decided to become an experimental physicist
1956 September, Ding Zhaozhong reluctantly bid farewell to his parents and went to the United States to study. I started my hard study at the University of Michigan. During his college years, Ding Zhaozhong was able to break the limitations of books to understand physical phenomena. He thinks "as Ding Zhaozhong at the press conference.
The most important thing for a scientist is to constantly explore things outside the textbook. "After three years of hard work, Ding Zhaozhong got a master's degree in mathematics and physics, and then studied at the Institute of Physics of the University of Michigan for two years, and got a doctorate in advance. He originally wanted to be a theoretical physicist, but two things prompted him to change his ambition. One is in the research institute, where he humbly consulted famous professors with profound knowledge such as Uberk Keyes, and they all liked this diligent China student. Professor Ulenbock told him that being an experimenter is more useful than being a theorist. The other is the first summer in college. Two professors are conducting an experiment in summer. Due to the lack of assistants, Ding Zhaozhong was invited to take part in the experiment. Since then, he has formed an indissoluble bond with experimental physics.
Concerned about the scientific development of the motherland
Although Ding Zhaozhong became an American citizen, he deeply knew that his roots were in China. For the development of high-energy physics in the motherland, he made great efforts to travel across oceans, made academic exchanges and visits to the mainland for many times, introduced the development of international high-energy physics, and strived to promote the cooperation between international physicists and Chinese physicists. Under his personal guidance and meticulous care, some China scientists engaged in research have obtained doctoral degrees in Europe and America. He not only trained a group of scientific research talents in experimental physics for China, but also worked hard to train graduate students in experimental physics for the motherland. He is currently employed as an honorary professor at China University of Science and Technology. Ding Zhaozhong said: "Since 4,000 years, China has made many important contributions in the history of human natural development, and will certainly make greater contributions in the future. I hope to train more talents for China within the time I can work. "
Characteristics of academic thought
Ding Zhaozhong's academic thought is characterized by attaching great importance to experiments in scientific research. He believes that physics is developed on the basis of close interaction between experiment and theory, and the basis of theoretical progress is that theory can explain existing experimental facts and predict new phenomena that can be confirmed by experiments. When an experimental result in physics contradicts the theoretical prediction, a revolution will take place in physics and a new theory will emerge. According to the history of physics and personal experience of nearly a quarter century, he pointed out that many important experiments, such as the discovery of parity non-conservation and parity compound symmetry (CP) in the decay of K mesons, the discovery of J particles and the discovery of high-temperature superconductors, have opened up new research fields in physics, but these experimental discoveries were made without theoretical interest in advance. Another example is the basic discovery of particle physics made by high-energy accelerator experiments in recent years. Except for W particles and Z particles, almost all particles were not predicted when the accelerator was built. He stressed that no theory can refute the experimental results. On the contrary, if a theory does not conform to the facts observed in the experiment, then it cannot exist. His view of attaching importance to scientific experiments is of great guiding significance to scientific workers.
Some fragments of personal experience
Professor Ding Zhaozhong is a world-famous experimental physicist. /kloc-0 was born in the United States on October 27th. 1936. His ancestral home was in Shandong Province, China, and he spent his middle school days in Taiwan Province Province. Ding Zhaozhong received her master's degree at 1960 and her doctorate at 1962. 1963- 1964 worked in CERN, 1964- 1967 worked in Columbia University. From 1967, Professor of Physics Department of Massachusetts Institute of Technology, and from 1977, he was elected as an academician of American Academy of Sciences.
1974, Ding Zhaozhong and American scientist Li Xite independently discovered the J/ψ particle. For this, both of them won the 1976 Nobel Prize in Physics. In Ding Zhaozhong's scientific experimental research work, there are several wonderful episodes that he experienced and was proud of.
The first clip took place in 1966, and Ding Zhaozhong redone one of the most important experiments in the world at that time, which was to measure the radius of electrons. The experimental results obtained by Ding Zhaozhong are consistent with the theory deduced by theoretical physicists, because as early as 1948, theoretical physicists concluded that electrons have no volume according to the theory of quantum electrodynamics. However, in 1964, experimental physicists got the experimental result that the electron radius was 10- 13 cm. Subsequently, many physicists have also obtained the experimental results with the electron radius of 10- 13 cm, which means that the experiment is not consistent with the theory. 1966, Ding Zhaozhong redone this experiment, which proved that the experimental results made by those scientists before were all wrong. Later, Ding Zhaozhong summed up the story and learned that "do experimental physics, don't blindly follow experts' conclusions".
Found the family of j particles.
The second segment is the discovery history of the J particle family. This discovery is praised as an important milestone in the history of physics development by the international high-energy physics community. 1In the early 1970s, physicists generally believed that there were only three kinds of quarks in the world, and all phenomena in the world could be explained by the theory of three kinds of quarks. 1974, Ding Zhaozhong put forward the experimental scheme of "looking for new particles and new substances", but unfortunately it didn't get the attention of most physicists. But he kept searching, and finally found a new particle-J particle in the experiment, whose life span is 10000 times that of ordinary particles, and recently discovered the J particle family. This experimental result proves that the three quark theory at that time was wrong. When Ding Zhaozhong realized this history, he always said, "You should have confidence in doing basic research. If you think it is right, you must persist in doing it; " Don't do it just because most people object, and don't care what others think. "
The third paragraph is the experiment of finding gluons. In physics, it is theoretically believed that the force between quarks is transmitted by gluons. If gluons exist, three jets will appear in the high energy electron-positron collision experiment. If gluons don't exist, there won't be three jets in the high energy electron-positron collision experiment, but only two jets. In the experiment, Ding Zhaozhong found three jets, which proved the existence of gluons. According to this "story", Ding Zhaozhong warned young scientists that "doing experimental physics should be fully prepared for unexpected phenomena".
The fourth part is the fruitful international cooperative research work carried out by Ding Zhaozhong in the Western European Nuclear Center in the past 20 years. This international cooperation group has more than 600 scientists from 19 countries, one third of whom are from the United States, one third from Europe and one third from Russia and other countries. This international cooperative experimental group has made important research progress, published a large number of academic papers, and 75 people obtained doctoral degrees. So why is this international cooperation supported by so many countries and so many scientists? Ding Zhaozhong later said in a speech: The most important thing in international cooperation is to choose the most important and interesting topics in the world to arouse the interest of scientists. Without interest, there is no point.
The fifth clip is an experiment to find the universe (AMS) composed of antimatter particles on the International Space Station. This experiment is the only one carried out on the International Space Station after many fierce competitions. The existence of antimatter was speculated by the British physicist P Dirac in 1928, and he won the Nobel Prize in 1933. If the universe came from the Big Bang, there were both matter and antimatter. Anti-Ding Zhaozhong in an interview.
Where is the universe of matter? All particles have antiparticles. Is there a universe made of antimatter? Ding Zhaozhong's AMS experiment is to answer these questions. If antimatter exists, it will release anti-helium or anti-carbon nuclei in space, and these anti-nuclei will pass through space and approach the earth, so we should be able to detect them in space. So this experiment needs to measure charged particles in outer space and determine it by measuring magnetic field. This experiment is also an international cooperative research work, involving scientists from 15 countries. The AMS experiment will be sent to the International Space Station by the American Space Shuttle 1 128 in October 2006, and the experiment will last for 3-5 years. Ding Zhaozhong put a lot of energy into this experiment. When the experiment made continuous progress, he once said with deep understanding that for a person doing experimental physics, the most important thing is to be curious, confident in what he is doing, and at the same time work hard.
autobiography
1976 Ding Zhaozhong, the winner of the nobel prize in physics, wrote an autobiographical article in 1980, "in exploration-a physicist's experience". At the beginning of this article, I quoted Marshal Ye Jianying's poem "Tackling Problems": It is not afraid of difficulties to attack a city, and it is not afraid of difficulties to attack a book. If there are obstacles in science, efforts can pass.
1936
Ding Zhaozhong said that he was born in the United States on1October 27th, 1936, but three months after his birth, his parents brought him back to China. He said, "Because of the situation in China at that time, I have always been a refugee, constantly fleeing from one place to another. Of course, this makes it impossible for me to receive any formal education. " /kloc-When he was 0/2 years old, he moved to Taiwan Province Province with his family before he went to middle school, so he cherished the opportunity to go to school. In high school, he especially liked physics and chemistry, studied hard and got good grades. One of his classmates once left him a message in his graduation photo album: "Your science can be said to be invincible in your class. I hope you can concentrate on attacking science and inventing several Shi Ding's laws! " After graduating from high school, Ding Zhaozhong was sent to department of mechanical engineering, national cheng kung university, Taiwan Province. 1956 when he was 20 years old, he went to the United States alone, entered the university of Michigan, and 1962 received his doctorate in physics. Ding Zhaozhong chose experimental physics as his main direction. 1972, he led his team to conduct a series of experiments in new york Brook National Laboratory to find new heavy particles. For the arduousness and complexity of the experiment, he once likened it to this: "In the rainy season, a city like Boston may have to drop 100 million raindrops in Qian Qian within one minute. If one of them has a different color, we must find the raindrop. "
1974
1974165438+1October 12, Ding Zhaozhong, who has worked in the laboratory for more than two years day and night, announced to the world that his team had discovered an unexpected new elementary particle-J particle, which has two strange properties: heavy mass and long life, so it must be.
1977
/kloc-0 In the autumn of 977, during Ding Zhaozhong's visit to China, he suggested to Deng Xiaoping that China Academy of Sciences send physicists to join his experimental team. During the ten years from 1978 to 1 when he welcomed the first batch of Chinese physicists, hundreds of people have come to his side. He said: "The cooperation with China is satisfactory." He also said: "In recent years, the quality of scientific research personnel in China has been greatly improved, from leaders to ordinary scientific and technological personnel, they are greatly younger. Great discoveries in science, especially in natural science, depend on young people. Like Newton, Faraday, Li Zhengdao and Yang Zhenning, their important discoveries were made when they were young. Therefore, I have high hopes for the young scientific and technological personnel of the Academy of Sciences. "
Three "I don't know"
origin
On June 7, 2004, the lecture hall of China Southern Airlines was packed. Teachers and students are listening to a lecture by Professor Ding Zhaozhong, a famous Chinese-American and Nobel Prize winner in physics, about finding antimatter and dark matter in space. After an hour's wonderful report, Professor Ding answered the students' questions as usual. "Do you think humans can find dark matter and antimatter in space?" I don't know. "Do you think the scientific experiment you are engaged in has any economic value?" I don't know. "Can you talk about the development direction of physics in the next 20 years?" I don't know. I don't know! And when you answer "I don't know", your expression is natural and sincere, and there is nothing you know you shouldn't say. All the students present were surprised. After a short silence, people began to whisper to each other. Soon, Professor Ding said with a smile, what you don't know must not be inferred subjectively, and it is difficult for the most advanced science to determine what is going on by judgment. A few short and plain words won warm applause from the audience and lasted for a long time.
suggestion
Coincidentally, Zhuangzi's Theory of Everything also records a story of three questions and three unknowns: "I ask you:' Is it the same for children to know things?' Said, "I hate to know this!" " The son knows what the son knows, but he doesn't know evil? Said, "I hate to know this!" " But things are ignorant and evil? Say:' I hate it! Although, try to say: I know what I mean by knowing, but I don't know evil. I don't know what I mean, but know evil? "There is no end to learning, but my life is endless. Knowing astronomy above and geography below, looking forward for 800 years and backward for 500 years, such a learned world is rare. So, knowing something is not a shame. Confucius has long taught people that "knowing is knowing, not knowing is not knowing". Ding Zhaozhong: "Love the motherland, love science and love honor."
I know that, but it's really hard to do it. Most people love face. They always like to show their knowledge. Even if they don't know, they don't want to teach others that they don't know. When things happen, as long as there is a little room for manoeuvre, they will not easily spit out the word "I don't know". Ding Zhaozhong is a scientist who enjoys a high reputation in China. It is said that he often answers "I don't know". It is the strong thirst for knowledge aroused by "not knowing" that makes him study tirelessly and become the shortest student from bachelor to doctor in the history of the University of Michigan. At that time, the annual tuition of the school was $65,438+0,000. Because of his outstanding performance, he got a subsidy from the school. During the six years from university to doctor, he only spent $65,438+$0,000 in tuition. It is also the strong curiosity aroused by "not knowing" that makes him explore the field of "not knowing" constantly, uncovering a lot of "not knowing" for mankind, and finally boarded the Nobel podium. Here is a negative fable: larks sing euphemistically, cicadas come to seek art, and as soon as she learns to speak, cicadas shout "cicadas-". For hundreds of millions of years, it will only be called "cicada", making some noise for the world. Therefore, if we want to do something like Professor Ding's, we should not regard ignorance as knowledge, but bravely open our mouths and spit out the words "I don't know", and then make great efforts to turn "I don't know" into knowledge. Trees soar and leaves fall back to their roots.
Science has no national boundaries, and a scientist will always belong to his own country. On June 18, 2005, Ding Zhaozhong, a famous physicist at home and abroad, returned to his hometown of Rizhao, Shandong Province with his wife and children to seek roots and worship his ancestors, realizing his long-cherished wish as an overseas traveler for many years. In the south gate of his hometown, Taoluo Town, facing thousands of old people who have been waiting for him for a long time, Ding Zhaozhong could not conceal his excitement. The west wing of Zhongdetang is the house where his father Ding and his mother Wang Juanying once lived. After visiting the West Wing of the White House, Ding Zhaozhong was invited to write an inscription as a souvenir, and Ding Zhaozhong asked his wife Susan to write an inscription first. Susan smiled knowingly. The blonde American lady sat down at an antique square table and wrote on white paper with deep affection in English: "Today is a special day for Shi Ding's family: the tree is high in thousands of feet, and the leaves fall to the roots. Susan. June 2005 18. " Ding Zhaozhong took the pen from her husband and asked her son Christopher to sign his name. Finally, under the inscription, he signed his name one by one: Ding Zhaozhong. Shi Dingjia is a famous family in Rizhao. His ancestors have repeatedly produced scholars and juren, and their books are rich. His grandfather Ding studied at Fudan University in Shanghai, and his father Ding studied at Shandong University in his early years as a civil engineer. In the early days of War of Resistance against Japanese Aggression, young Ding Zhaozhong spent an innocent childhood in his hometown. Christopher Ding, the only son of Ding Zhaozhong, returned to his hometown with his father. 19-year-old tall guy, sophomore at his father's alma mater, the University of Michigan. Grandpa Ding specially gave his beloved grandson a Chinese name: Ding. The old man also gave Ding Zhaozhong's other two children Ding Mingmei and Ding Mingming Chinese names. Ding is full of curiosity about everything in his parents' hometown. Everywhere, Ding Zhaozhong took pains to explain to his son in English. He told his son, "Americans like to go to Europe to find their ancestors;" And you came to China to look for your ancestors. "In Ding Zhaozhong's heart, how he longed for his son to know and love his hometown as much as he did! Standing in front of grandpa Ding's grave, his heavy face was relieved. Memories 1985 Ding Zhaozhong, a teenager who left home, returned to his hometown to visit relatives for the first time after more than 40 years. On June 14, 2002, Ding Zhaozhong said, "I really should bring my son back and show him that his roots are here." Now, Ding Zhaozhong, whose sideburns are gray, has finally returned with his son. After writing the elegiac couplet on the wreath, Ding Zhaozhong took his wife Susan's hand, stared at his son and said slowly in English, "Your roots are here." Your roots are here. ) "The black tombstone is engraved with the inscription written by Ding Zhaozhong: I miss my grandfather, who encouraged my family to make contributions to the world. At the end of his short trip to his hometown, Ding said with emotion: "This time, I returned to my father's and grandfather's hometown, visited my former residence, and learned about the life of several generations here. This will be the most unforgettable experience in my life. "