After listening to the plan of the person in charge on the stage, Xu Chuan looked at Qin Anguo sitting next to him with a strange expression.
The mass catapult, the Nantianmen Project, and the space carrier were all things he had talked about with Wen Yuanhang a week ago.
I didn’t expect that I would be directly cited as a publicity today.
Noticing Xu Chuan's gaze, Qin Anguo turned around and smiled at him, saying, "I have to thank Academician Xu for your suggestion. Comrade Wen Yuanhang reported on these directions and developments after he came back."
"After discussion at the internal meeting of Xinmen, everyone felt that your suggestion was quite good, so they made a more detailed plan and used it in today's exchange meeting."
"After all, today's exchange meeting is open to the public, and with such a large-scale report, it must be able to attract some attention from the United States."
Xu Chuan touched his chin, thought for a moment and then said: "To be honest, I think the plan you came up with might actually be feasible. Things like mass catapults can indeed be done in theory.
.”
Hearing this, Qin Anguo asked curiously: "How do you say that?"
Xu Chuan smiled and explained: "If it is just a simple manned spaceflight and lunar exploration project, there is really no need to build a large mass catapult."
"After all, the spacecraft required to carry out a manned space flight and lunar exploration project should theoretically not exceed one hundred tons."
"Even if we can't directly send a 100-ton spacecraft to space at once, we can still do it in several batches, and it won't cost too much money."
"But if you want to carry out large-scale lunar exploration, fire detection, or even establish a permanent scientific research and residential foundation on it, a simple and lower-cost transportation method is quite necessary."
"If you look at it from a long-term perspective, building a large-scale mass accelerator is still a good choice."
Qin Anguo thought for a while and asked: "If we build such a project, how much money and time will it take? Can it be done with current technology?"
Hearing this, Xu Chuan thought for a while and said: "Mass projectors are generally composed of giant electromagnetic guide rails, or they may be coils, vacuum pipes and power supply systems."
"Any one of these three has huge engineering difficulties. The electromagnetic guide rail or coil is best composed of superconductors. Its huge superconductor requirements and corresponding low temperature requirements are almost unacceptable at present."
"However, as long as superconducting materials are further developed, this shortcoming can theoretically be solved."
"Secondly, the engineering difficulty of the vacuum super pipeline that is several kilometers vertical is also there. However, it can be built with the help of mountains such as Mount Everest. With the structural support of the mountain, this is not the most important."
"As for the energy supply problem, after controllable fusion technology is solved, electric energy is the easiest problem to solve."
"So in theory, this is indeed feasible."
"As for the funding, I did a simple calculation and it is estimated that this project will start at one trillion RMB."
"But the advantage is that after it is built, the price of each launch will be quite low. With this kind of thing, space activities can be carried out on a large scale in the future."
"If you are interested, I can ask someone to make a plan and budget for you after I go back."
Hearing the budget revealed by Xu Chuan, Qin Anguo smiled bitterly, shook his head and said: "Trillion, impossible, at least not now. It is impossible for the Development Committee to pass a project with this level of budget."
If it is controllable nuclear fusion, perhaps in the period when hope is seen, such as the demonstration reactor, this level of investment can still be passed. After all, China is extremely hungry for energy and spends 100,000 yuan on fossil fuel imports every year.
The amount far exceeds this figure.
But in aerospace engineering, it's almost impossible.
Even if the country can allocate so much funds, it is impossible to invest it in this kind of project. Isn't it good to use it to mine resources on the earth? Does it have to go to space?
Why, the iron in space is better than the iron on earth?
Xu Chuan smiled and said: "In fact, compared to cultivating this on the earth, I am more optimistic about cultivating it on the moon."
"For mining helium-III mineral deposits on the moon, due to the low gravity and airless environment, a large-scale mass projector is not needed to throw large-mass items to the earth."
Qin Anguo thought for a while and said with a smile: "This idea is quite special. I suggest you study it after I go back."
The two chatted, and the exchange meeting on the stage came to an end.
Apart from the representatives from the Academy of Sciences and the Institute of Science and Technology, representatives from major aerospace fields and even some private enterprises that have nothing to do with aerospace, such as goose factory, cat factory and other enterprises also came to the stage to give exchange reports.
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The former is mainly to share and exchange some technologies in the aerospace field, and to promote business and visibility for their own companies, etc.
The latter said that he had the idea and budget to enter the aerospace field, or announced a satellite network plan or something.
Including Xu Chuan himself, at the request of Chairman Qin Anguo, he came to the stage to make a report on the development and direction of the aerospace field.
Of course, he did not speak much, mainly focusing on the field of electromagnetic propulsion.
After all, since the last time I talked with Academician Yang Hong, the aerospace electromagnetic propulsion system has been his preferred aerospace engine technology.
However, his fame lies here, and the direction he mentioned has been recorded by many people in academia, industry, and even business circles.
All in all, industry and business circles can present themselves, meet partners, etc. at exchange meetings.
More importantly, investments in the aerospace field can be tax deducted at a ratio of one to two.
This is undoubtedly great news for those companies that pay large amounts of tax.
Enterprises such as Goose Factory have their own demand and dependence on satellites. This time the country has subsidized scientific research funds in the aerospace field in disguise, which will undoubtedly save them a lot of money.
This chapter is not finished yet, please click on the next page to continue reading the exciting content! The country has also promoted the development of the domestic aerospace field through this exchange meeting.
Of course, more importantly, through this kind of exchange meeting, the disclosure of China's goals and plans in the aerospace field will help attract the attention of Western countries led by the United States and drag them into the aerospace field.
In order to slow down the other party's research progress in the field of controllable nuclear fusion, maintain its leading edge, expand China's influence in the international community, etc.
Today's meeting can be said to be a win-win situation for everyone present.
.......
For this kind of large-scale exchange meeting, in addition to the daytime exchanges, there will also be an exchange party in the evening for guests attending the meeting to get to know each other.
At the party, many people looked for that young figure in the venue with wide eyes. However, to everyone's regret, that person did not come to the party.
At this moment, Xu Chuan has returned to Beihai Hotel.
For him, attending such a party did not make much sense. He might as well come back and study mathematics.
The research on correlation effects and superconductivity in multi-orbital strongly correlated systems has not yet been completed, so he must hurry up and finish this.
After all, superconducting materials with high critical magnetic fields are the basis for miniaturized controllable nuclear fusion technology and aerospace electromagnetic propulsion systems.
In the hotel room, Xu Chuan, who once again ruled out a way, put down the pen in his hand, raised his head and silently looked at the white ceiling.
Over the past few days, he has continuously eliminated many different routes through mathematical methods, and has also tried several different methods to calculate.
But in the end, no good results were obtained.
However, if the problem of studying correlation effects and superconductivity in multi-orbital strongly correlated systems was really so easy to solve, it would not be a century-old problem in physics.
With a long sigh of relief, Xu Chuan lowered his head to look at the manuscript paper on the table and began to think again.
"Most of the time, the strongly correlated system of electrons is basically started or described from the perspective of condensed matter, but quantum chemistry can also explain this. Maybe we can try it from quantum theory?"
Staring at the manuscript paper on the table, Xu Chuan fell into deep thought.
"Strictly speaking, the single-electron (mean field) approximation does not mean that the interaction between electrons is ignored, but that the interaction between electrons is considered in the form of a mean field, that is, the two-body operator is passed
Trace with the single particle density matrix is converted into a single operator."
"But the mean field approximation does not mean that there is no correlation. Since the Hartree-Fock wave function is antisymmetric (Slater determinant), there is actually a correlation between electrons with the same spin. This is called the Fermi correlation."
"So the real missing correlation effect in the mean field approximation is the so-called Coulomb correlation."
"If you want to calculate this kind of general coupling, you have to start with the specific form of the wave function. The approximate wave function used by the mean field approximation Hartree-Fock is called the Slater determinant, which is the product of the single-electron wave function and is then antisymmetric and satisfies Pauli
incompatible."
Thinking about it, Xu Chuan involuntarily picked up the signature pen on the table again and wrote on the manuscript paper:
[|Ψ>=c0|Φ> ∑i,aCai> ∑ij,abCab/ij> ···(eqn 1)】
Starting from the ground state configuration, the single-electron wave function |Φ?|\Phi\rangle|\Phi\rangle is a good approximation of the multi-body wave function |Ψ?|\Psi\rangle|\Psi\rangle, indicating the Coulomb correlation
Very small.
In weakly correlated systems, the mean field approximation can qualitatively describe many properties of the system, but there are some quantitative shortcomings. These quantitative shortcomings are derived from the contribution of those excited configurations that account for a small proportion.
In other words, it can be promoted!
Perhaps, starting from the field of quantum chemistry, it is really possible to find a mathematical path to correlation effects in multi-orbital strongly correlated systems.
Staring at the data on the manuscript paper, Xu Chuan's eyes flashed with excitement.
He may have found a breakthrough.
But it’s not yet known how far this mouth will allow him to go.
........
PS: There is another one tonight, please give me a monthly pass!
