The Science Fiction World of Xueba

Pang Xuelin talked with Katherine Murphy for an afternoon.

女人 This woman is worthy of being a senior reporter for Time Magazine, and she is in control of the rhythm of the chat.

From math to life, from life to business, until 4:30 pm, this interview lasted more than three hours.

Subsequently, Pang Xuelin coordinated with the photographers of Time Magazine to pose Pose for more than half an hour to complete the pose.

"Teacher Pang, thank you very much for your cooperation today. May I have the pleasure to invite you to dinner?"

Murphy got up and shook hands with Pang Xuelin, little fingertips scratched in Pang Xuelin's palm without a trace, looking at Pang Xuelin with a smile.

Xi Pang Xuelin quietly retracted his hand, and just about to say no, Edward Witten hurriedly came in at the cafe door.

"Mr. Pang, sorry for not disturbing you?"

Edward Witten looked anxious.

教授 "Professor Witten, all right, I just finished the interview, what's wrong?"

Pang Xuelin wondered.

Witten said: "I want to talk to you about Ponzi geometry. I wonder if it is inconvenient for you now?"

She Pang Xuelin shrugged towards Catherine Murphy, with a sorry smile: "Ms. Murphy, I'm sorry, it seems that I can't have dinner with you at night."

Murphy raised an eyebrow, brushed down a string of numbers on the notebook, tore off that page and handed it to Pang Xuelin, smiling: "This is my mobile phone number, I will stay in Princeton for a few days , Welcome to come to me if you have time! "

He said, Murphy picked up the recording pen and backpack, blinked at Pang Xuelin, and said to Edward Witten: "Professor Witten, I will not disturb you and Teacher Pang."

This woman ...

She Pang Xuelin shook her head and smiled, and said to Witten, "Professor Witten, is there anything you can do to me?"

Edward Witten looked around and said, "Mister Pang, let's talk in a quiet place."

Pang Xuelin said: "Okay, go to my room!"

I came to the executive suite where Pang Xuelin lived, and the two sat down in the office area.

Geng Huan gave each of them a cup of coffee, and then quietly exited the room.

Witten took out a stack of manuscript papers filled with formulas from the small bag he carried with him and said, "Mister Pang, do you know the theory of superstrings?"

Pang Xuelin frowned slightly, her eyes narrowed slightly.

The most important reason why Edward Witten has such a famous name in theoretical physics is that he proposed the M theory based on the theory of superstrings in 1995. The theory of hypergravity in dimensional space is unified into a single mathematical structure.

This work initiated the second superstring revolution. In later generations, M theory is considered to be the ultimate theory that is most promising to solve the essential interaction between matter and energy.

But at this time, Edward Witten should not have completed the research of M theory. Did his Ponzi geometry give him any inspiration?

Pang Xuelin said: "I probably know some. In physics, one of the basic problems to be solved is how to realize the quantization of gravitational force, and to interact gravitational forces with the other three basic interactions in nature (electromagnetic force, strong interaction, (Weak interaction), the superstring theory is currently the only theory that can achieve the above requirements. "

Witten was a little surprised: "Well, Pang, you must also know that although superstring theory seems to already describe the ultimate unity between interactions in nature, there are still several problems. First, there are currently five A kind of self-consistent perturbative string theory in the sense of quantum mechanics. They are two IIA and IIB, a hybrid string theory whose specification is Apin (32) / Z2, a hybrid string theory whose specification group is E8 × E8, and A type I string theory whose specification is SO (32). They are equivalent in the physical sense. We cannot choose one theoretically and exclude the existence of the other four superstring theories. "

"Second, the self-consistency of the five kinds of perturbed strings requires ten-dimensional space-time and space-time supersymmetry. The natural standard energy is 10 ^ 19GeV. In the foreseeable future, we cannot make such a high-energy accelerator pair String theory is directly tested. Therefore, the smallest test requirement is that some kind of perturbative string theory can give observable physics in four dimensions, such as the standard model of particle physics ... "

"The third problem is that for an ultimate theory describing all physical laws in nature, in addition to some possible basic constants such as the speed of light, Planck's constant, and string tension plus possible initial values ​​or boundary conditions, other quantities should be determined by The dynamics of the theory are determined. In particular, the vacuum state of the theory should be determined by its dynamics. "

"But the perturbation string theory assumed from the beginning that the space-time was flat and required that the interaction of the strings be small in order for the string perturbation to be valid. These assumptions are contrary to the ultimate theoretical requirements. Therefore, there are currently five kinds of Perturbation string theory is a limit theory, so it is unlikely to be the ultimate theory. "

"Fourthly, from the perspective of the perturbed string theory, the eleven-dimensional hypergravity theory seems to have nothing to do with describing the real world. We know that the low energy limits of the five perturbed string theories give corresponding supergravity theories, while the lower-dimensional ones The theory of supergravity ~ www.readwn.com ~ corresponds to the compacted superstring low-energy theory. If the perturbative string theory is really the ultimate theory, then we have no way to explain the existence of the eleven-dimensional supergraviton . "

"But if we consider the one-dimensional space dimension of eleven-dimensional space-time as an extremely small circle, eleven-dimensional hypergravity now gives one of the low-energy effective theories of superstrings. The radius of this small circle is The strength of the interaction of this string theory is directly proportional. From this we can see that the eleven-dimensional supergravity should be related to the low-energy theory of this non-perturbative theory of strings. In other words, we only know the non-perturbation of string theory. Nature can explain eleven-dimensional hypergravity. "

Xi Pang Xuelin said with interest: "Professor Witten, what do you mean ...?"

Edward Witten's eyes gleamed, saying, "I have been seeking a new theory for the past few years to unify the five superstring theories and the eleven-dimensional supergravity theory, but I have never found a suitable mathematical tool. To describe it, but in the past two days through the study of Ponzi geometry, I have a vague sense of the dawn of the new theory. But my research on Ponzi geometry is still quite shallow at the moment, and I need your help, or we cooperate in research, What do you think about finding a new ultimate theory together? "

Pang Xuelin looked at Edward Witten's eyes, pondered for a moment, and stretched out his hand and laughed, "Happy cooperation!"