After listening to the plan of the person in charge on the stage, Xu Chuan looked at Qin Anguo sitting beside him with a strange expression.

The mass catapult, the Nantianmen plan, and the aerospace carrier were all things he had talked about with Wen Yuanhang a week ago.

I didn't expect to be directly pulled up as propaganda today.

Noticing Xu Chuan's gaze, Qin Anguo turned around and smiled at him, and said, "I have to thank Academician Xu for your proposal, after Comrade Wen Yuanhang came back, he reported on these directions and developments." ”

"After the discussion of the internal meeting of the company, everyone felt that your suggestion was quite good, so they made a set of detailed plans and used them in today's exchange meeting."

"After all, today's exchange meeting is open to the public, and with such a large-scale report, how can it attract some attention from the United States."

Xu Chuan touched his chin, thought for a while, and said, "To be honest, I think the plan you made may be really feasible." Something like a mass catapult is theoretically possible. ”

Hearing this, Qin Anguo asked curiously, "What do you say?" ”

Xu Chuan smiled and explained: "If it is just a simple manned spaceflight and lunar exploration project, it is really not necessary to build a large mass catapult. ”

"After all, the spacecraft needed to carry out a manned space flight and lunar exploration project will theoretically not exceed 100 tons."

From the ground state configuration, the single-electron wave function |Φ|\Phiangle|\Phiangle is a good approximation of the many-body wave function |Ψ|\Psiangle|\Psiangle, indicating that the Coulomb correlation is small.

"So, the correlation effect that is really missing from the mean field approximation is the so-called Coulomb correlation."

"Secondly, there is also the difficulty of engineering the vertical multi-kilometer vacuum super pipeline, but this can be built with the help of mountains like Mount Everest, which are supported by the structure of the mountain, which is not the most important."

Including Xu Chuan himself, at the request of Minister Qin Anguo, he came to the stage to make a report on the development and direction of the aerospace field.

In order to delay the progress of the other party's research in the field of controlled nuclear fusion, maintain its leading edge, and expand China's influence in the international community, etc.

"If we want to calculate this kind of broadness, we have to start with the specific form of the wave function. The approximate wave function used by Hartree-Fock for the mean field approximation is called the Slater determinant, which is the product of the single-electron wave function and then antisymmetric and satisfies Pauli's incompatibility. ”

Hearing Xu Chuan's explosive budget, Qin Anguo smiled bitterly, shook his head and said, "Trillions, impossible, at least not now." It is not possible for the development committee to pass a project with a budget of this level. ”

Qin Anguo thought for a moment and asked, "If such a project is built, how much money and time will it take?" Can the current technology do it? ”

However, his fame is here, and the direction he said has been recorded by many people in academia and industry, and even in business.

In addition to the representatives of the Academy of Sciences and the Science and Technology Institute, representatives of major representatives in the aerospace field and even some private enterprises that have nothing to do with aerospace, such as the Goose Factory and the Cat Factory, also came to the stage to make exchange reports.

More importantly, investment in the aerospace field can be tax deductible on a one-to-two basis.

Over the past few days, he has mathematically eliminated several different routes and tried several different methods to calculate them.

"As for the funding, I made a simple calculation, and this project is estimated to start with trillions of RMB."

This is undoubtedly great news for those businesses that pay large amounts of taxes.

The latter said that he had the idea and budget to enter the space field, or announced what satellite network plan or something.

"As for the energy supply problem, after the controlled fusion technology is solved, electric energy is the easiest trouble to solve."

The two chatted, and the exchange meeting on the stage also came to an end.

All in all, both industry and business can present themselves at networking sessions, meet partners, and more.

In the weakly correlated system, the mean field approximation can characterize many properties of the system, but there are some quantitative deficiencies, which come from the contribution of those small excitation configurations.

Enterprises such as the goose factory themselves have their own demand for and dependence on satellites, and this time the state has subsidized scientific research funds in the field of aerospace in disguise, which can undoubtedly save them a lot of money.

Even if the state were able to spare such a large amount of money, it would not be possible to invest it in such a project. Isn't it good to use it to tap the resources of the earth? Do you have to go to space?

Today's meeting can be said to be a win-win situation for everyone present.

"However, as long as superconducting materials are further developed, theoretically this shortcoming can be solved."

After all, since the last time I talked to Academician Yang Hong, the aerospace electromagnetic propulsion system is his preferred aerospace engine technology.

"If you build a large mass accelerator from a long-term perspective, it's still a good choice."

This kind of large-scale exchange meeting, in addition to the daytime exchange, there will also be a communication party in the evening, for the guests to get to know each other.

Qin Anguo thought for a moment and said with a smile: "This idea is quite special, I propose to study it after I go back." ”

However, if the problem of correlation effect and superconductivity in multi-orbital strongly correlated systems is really so easy to solve, it will not be a problem of the century in the physics world.

Hearing this, Xu Chuan thought for a moment and said, "The mass projector is generally composed of a giant electromagnetic guide rail, or it may be a coil, a vacuum pipe and a power supply system. ”

Of course, more importantly, through this kind of exchange meeting, the disclosure of China's goals and plans in the aerospace field is conducive to drawing the attention of Western countries led by the United States and dragging the other side into the track of the aerospace field.

【|Ψ>=c0|Φ>+∑i，aCai>+∑ij，abCab/ij>+··· （eqn 1）】

In the hotel room, Xu Chuan, who once again ruled out a way, put down the pen in his hand and looked up at the white ceiling silently.

With a long sigh of relief, Xu Chuan looked down at the manuscript paper on the table and thought about it again.

At the party, many people opened their eyes to look for the young figure in the venue, but to everyone's regret, that person did not come to the party.

The study of correlation effects and superconductivity in multiorbital strongly correlated systems has not yet been completed, and he has to hurry up to get this done.

But in the end, nothing good came of it.

"The strongly correlated system of electrons, for the most part, is basically from the perspective of condensed matter or described, but quantum chemistry can also explain this, maybe we can try it from quantum theory?"

Why, is iron in space better than iron on Earth?

Xu Chuan smiled and said, "Actually, compared to cultivating this on the earth, I am more optimistic about cultivating on the moon." ”

"Strictly speaking, the single-electron (mean field) approximation does not mean that the interaction between the electrons is ignored, but that the interaction between the electrons is considered in the form of the mean field, that is, the binary operator is transformed into a single-body operator by tracing with the single-particle density matrix."

"Even if we can't directly send a 100-ton spacecraft to the sky at one time, we can do it several times, and the cost will not be too much."

"But the mean field approximation does not mean that there is no correlation, and since the Hartree-Fock wave function is antisymmetric (Slater determinant), there is actually a correlation between electrons with the same spin, which is called the Fermi correlation."

"But if you want to carry out large-scale lunar exploration, fire exploration, and even establish a permanent scientific research and residential base on it, a simple and less costly transportation method is quite necessary."

But aerospace engineering is almost impossible.

"But the advantage is that after it is built, the price of each launch is quite low, and with this kind of thing, it can be carried out on a large scale in the future."

"For the excavation of helium III deposits on the moon, because of the low gravity and airless environment, it is not necessary to have a very large mass projector to throw a large mass item to the earth."

If it is controlled nuclear fusion, perhaps in a period of hope, such as a demonstration reactor, this level of investment will still be passed, after all, China is desperate for energy, and the amount spent on fossil fuel imports alone far exceeds this figure every year.

For him, there is not much point in attending such an evening, and it is better to come back and study mathematics.

That is, it can be promoted!

The former is mainly to share and exchange some technologies in the aerospace field, to attract business and popularity for their own enterprises, and so on.

After all, superconducting materials with high critical magnetic fields are the basis for miniaturized and controllable nuclear fusion technology and aerospace electromagnetic propulsion systems.

Of course, he didn't speak much, focusing mainly on the field of electromagnetic propulsion.

Thinking about it, Xu Chuan involuntarily picked up the signature pen on the table again, and wrote on the manuscript paper:

At this moment, Xu Chuan has returned to the Beihai Hotel.

Staring at the manuscript paper on the table, Xu Chuan fell into deep thought.

"And any of these three have huge engineering difficulties, and the electromagnetic guide rails or coils are preferably composed of superconductors, whose huge superconductor requirements and corresponding low temperature requirements are almost unacceptable for the time being."

The country has also promoted the development of the domestic aerospace field through this exchange meeting.

"If you're interested, I'll have someone make a plan and budget for you when I get back."

"So in theory, it's doable."

Perhaps, starting from the field of quantum chemistry, it is really possible to find a mathematical path to the correlation effect in multi-orbital strongly correlation systems.

Staring at the data on the manuscript paper, Xu Chuan's eyes flashed with a look of excitement.

He may have found a breakthrough.

It's just that how far this mouth can make him go, I don't know for the time being.

PS: There is one more at night, ask for a monthly pass!