At this time, Witten had not yet reached the level of being called "the smartest man in the world" as he would later be, and he was just a researcher in his twenties and about thirty.

Witten was born in Maryland on August 26, 1951. He studied history and economics at Brandeis University, graduating in 1971 and running for president in 1972. He then went to Princeton University to study physics, where he received his master's degree in 1974 and his Ph.D. in 1976. He then worked as a researcher at Harvard University and became a professor of physics at Princeton University in 1980. Professor of Physics at the Institute for Advanced Study in Princeton since 1987.

Edward Witten's most outstanding achievement lies in his achievements in string theory, Witten's goal is to establish the grand unified theory, and his method is largely topological, especially his understanding of Morse's theory, De. Ram and Hodge theories, especially the indicator theorem, give new formulations and proofs. He gives Witten invariants, and the results take Jones's inequality, Flor's invariant, and Donaldson's invariant as their special cases. In the 1990s, Witten's work was even more brilliant: first, in 1994, it introduced the Cerberg-Witten invariant with Seberg, which dwarfed many of the invariants of the past by solving linear equations. The second is to establish M theory in 1998 and unify different forms of string theory into a complete framework. He has published more than 200 papers and is known as one of the most influential physicists of our time.

There is an interesting saying about Witten, that is, the history student who does not want to win a Fields Medal is not a good physicist, and thus becomes a great legend in the scientific community.

Although Lie group and Lie algebra are the knowledge points and research objects of group theory from a literal understanding, Lie groups and Lie algebra often use many topological methods in their research, and it is not impossible to say that they are the research objects of topology.

Since Witten began to be a professor in the Department of Physics at Princeton University, he began to study mathematical physics, especially in the study of topology. Recently, he has been trying to use mathematics to deal with some difficult problems in physics, and after achieving good results, he has increased his investment in mathematics.

With the idea of being close to the water, Witten took the opportunity of the exchange of the mathematics department of Princeton University to join the afternoon tea discussion of the mathematics department as a professor of the physics department, which seemed a little different.

But Witten is a professor after all, so no one rejects him, and there are many people who should talk and chat with him, but after all, it is not the same major, so there is still a little difference between the two, so although it is a Princeton Mathematics Department afternoon tea discussion full of elites, it is difficult for Witten to find a young man with the same views and ideas as him after participating again and again, which can't help but make him a little disappointed.

When he was about to go back to continue his research and prepare for the class, Witten inadvertently passed by Junxin and Ars, and the two of them were interested in the discussion of Li Qun and Li algebra, so they stopped and listened to the research and discussion between Junxin and Als.

I have to say that after hearing this, Witten suddenly felt a lot of gains. In fact, since the middle of the 20th century, the biggest task of the physics community has actually been to complete the unified field theory, which is the so-called grand unified theory. It was in the opinion of people at that time (and in fact most people believe today) that everything in physics or nature could be calculated using quantum mechanics and relativity.

However, the theory of relativity and quantum mechanics have a great role in their respective fields, but they are fundamentally different, and how to unify them has become a major and even the ultimate topic for physicists today, and Edward-Witten is no exception in this regard. It's just that the direction chosen by Witten is a breakthrough in the direction of mathematics.

"Professor Witten, I was a mathematics student at Mizuki University before I came to Princeton, but I also developed a great interest in physics. However, because of the professional problems, I am more concerned about some problems related to mathematics in physics or even derived from mathematical calculations. Recently, his main research direction is string theory, which has flourished in physics for a while. ”

"Oh? How much do you know about string theory? Sure enough, Witten was quickly attracted by Junxin's words.

"I think today's string theory can be called Bose string theory, and the string theory established today mainly describes the scalar field of bosons acting under strong interactions, breaking through the traditional concept of physics that particles are the smallest units of physics. Thus converting a zero-dimensional point into a one-dimensional string, which is a breakthrough concept. ”

"Well, you're right!" Witten sighed, "But the Bose string theory also has a natural huge flaw. ”

"One is that it simply describes scalar bosons, and does not introduce fermions into the framework; second, it does not include the gauge symmetry found in general quantum field theory; The third is that when we study its mass spectrum, it is found that its vacuum state is a group of unstable tachyns with a mass square of less than zero. So when they realized the problem, physicists abandoned the concept. ”

"But I think there is a lot of room for development in string theory, and some time ago I solved a mathematical model, and when I used my mathematical model to explain string theory, a very interesting idea appeared." Junxin said unhurriedly.

"Oh? What is it? ”

"When I used my mathematical model, I found such a phenomenon when solving graviton-related problems, that is, although my model could not find a boson with a spin of 2 and a mass of 0, the conclusion was very consistent with the relativistic model."

"Oh? It's true? Witten asked excitedly.

"Yes, this paper was sent to Physical Review Letters before I came to Princeton, and I think you'll see it soon, but I might as well share my thoughts here."

"Thanks, I'm interested in your train of thought!" Witten motioned for Junxin to continue.

Junxin smiled apologetically at Als, and then began to explain to Witten the methods and ideas he had used in that paper. Although Als on the side was a little bored, he didn't leave, and listened carefully to Junxin's article ideas like Witten.

After Junxin finished speaking, Witten said after a period of silence, "Your train of thought is right, just now after I deduced, I found that there is no problem with your theory and model, it seems that string theory should be more than what we see." ”

"In fact, after solving the graviton problem, while I was working on the path integration problem in mathematics, I came up with an idea that I found interesting: Can we integrate existing string theory with other theories? We know that the boson is actually an elementary particle representing energy, and the fermion is an elementary particle representing the mass of matter, I just said that the current string theory is just the Bose string theory, you just said that the string theory only contains scalar bosons, and does not include fermions, if the current supersymmetry theory is used to fuse string theory, can we break through the inherent defects of string theory, you see, what about this idea? ”

"Is this a superstring?"