Pang Xuelin smiled and shook his head, he didn't have the idea of talking to Baker.

At this stage, physics research can only be a castle in the air, without experimental verification, no matter how big the brain hole is, it is meaningless.

Moreover, in these papers, he did not find a few new theories that could experimentally avoid the interference of the Zhizi, let alone a way to shield the interference of the Zhizi.

However, Pang Xuelin also knows very well that this kind of thing is not in a hurry.

According to his plan, before the law of the dark forest is announced, it is best to find a way to shield Zhizi, and if he can't find it, as long as his plan can be implemented smoothly, the overall impact on the future development of mankind will not be great.

It took nearly half a month for Pang Xuelin to have a general understanding of the scientific and technological progress in the past five years.

In general, space is progressing rapidly, but it is basically the result of piling up resources.

Human space activities are still inseparable from chemical rocket power, and there is no alternative to chemical rocket power in the foreseeable future.

Elsewhere, the density of integrated circuit transistors has quadrupled from five years ago, but is close to the limits of Moore's Law.

And because of the blockade of Zhizi, quantum computers don't have to think about anything, and scientists are currently considering replacing the original silicon-based chips with carbon-based chips.

In the fields of biomedicine, new energy, and modern agricultural technology, there are even signs of regression.

New energy, in particular, has suffered a devastating blow.

At present, countries have generally stopped considering climate change, global warming and other issues, and have begun to turn a blind eye to environmental pollution, those expensive solar and wind energy are no longer favored by governments, and low-cost thermal power stations and nuclear power plants have become the first choice for power sources.

Those solar and wind energy companies that were originally well-developed have collapsed one after another over the years, and only a few are still holding on, but they can't last long.

In the field of agriculture, there have been signs of worsening climatic anomalies in recent years, but they have not yet had a particularly significant impact on agricultural production.

Pang Xuelin estimates that this effect will not become apparent until at least 20 or even 30 years later.

On this day, Pang Xuelin handed over a list to Cheng Xin and said: "Inform the people on the list that they will have a meeting at the Transwarp Institute for Advanced Study in three days, and some of them are on a business trip in other places, so they must rush back in three days!" ”

Cheng Xin was slightly stunned, glanced at the names on the list, nodded and said, "Okay, I'll notify you immediately." ”

Pang Xuelin asked Cheng Xin to inform that they were all experts in the field of nuclear physics and materials who had been recruited by Kantor in recent years.

In the past five years, international research on nuclear fusion has mainly focused on multinational cooperation based on ITeR, compared with the engineering of multilateral cooperation before the three-body crisis, the efficiency of ITeR has been several times higher, but the technical indicators of ITeR have also increased a lot.

As a result, even after five years, ITeR progress is still not satisfactory.

Pang Xuelin is ready to start anew and build a fusion reaction experimental reactor in Star Ring City.

Controlled nuclear fusion is known as the ultimate energy source for mankind, one liter of seawater contains about 30mg of deuterium, and the energy that can be released through the fusion reaction is equivalent to the energy of more than 300 liters of gasoline, and the reaction products are non-radioactive.

In other words, 1 liter of seawater can produce the equivalent of 300 liters of gasoline. A 1 million kW nuclear fusion power station consumes only 304 kg of deuterium per year. It is estimated that 4.5 billion tons of deuterium is naturally present in seawater, and the conversion of deuterium in seawater into energy through nuclear fusion is enough to meet the energy needs of mankind for billions of years in the next few billion years at the current level of world energy consumption.

Not to mention, there is a staggering amount of helium reserves on the moon that are suitable for second-generation fusion reactors.

However, in order to achieve a controlled nuclear fusion reaction, there are many technical difficulties.

First, at tens of millions or even hundreds of millions of degrees of high temperature, some of the nuclei in the plasma gas may undergo fusion reactions, and the higher the temperature, the faster the fusion reaction will proceed.

Second, sufficient confinement, that is, confinement of the plasma at high temperature in a certain area and keep it for enough time to make it fully fused.

Third, the density is quite low. Plasma gas at high temperature has a high pressure, so the gas in the container should be pumped into a considerable vacuum, so that the number of particles per unit volume cannot exceed 10 to the 15th power, which is equivalent to tens of thousands of the density of the gas at room temperature.

Fourth, ensure self-sufficiency. The instability of the plasma at high temperatures makes it confined only for a short time. In order for a sufficient number of plasma gases to fuse and sustain themselves, there must be a requirement between the density of the plasma gas involved in the reaction and the time to achieve reliable confinement to it, namely the Lawson condition. For example, the conditions for the deuterium-tritium fusion reaction to be realized are: the plasma temperature reaches 200 million degrees, the particle number density reaches 10^20m^-3, and the energy confinement time exceeds 1s.

Fifth, and most difficult, and important, is the nuclear material for the production of fusion reactors.

At present, the first three technical hurdles have been largely overcome, and if the ITeR project is progressing well, the fourth problem is expected to be solved in the next two decades, and only the fifth is still far away.

Fermi once said that the success or failure of nuclear technology depends on the behavior of materials under strong radiation fields in reactors.

Although this sentence is timely, it is aimed at fission reactors, but it is just as effective for fusion reactors, and to some extent, it is even the key to the success of controlled nuclear fusion.

In commercial tokamaco fusion reactors, the first wall material, the layer facing the plasma, needs to meet a number of stringent requirements:

The first is low tritium retention.

Compared to the legendary helium nuclear fusion, the most controllable fusion reaction is the deuterium-tritium reaction.

However, tritium (T) has a short half-life and there is no natural tritium. It is almost impossible to manufacture artificially, hundreds of millions of dollars a kilogram, and there is still no market. Therefore, tritium in fusion reactors needs to be recycled.

At present, the main method of the scientific community is to use multiplied neutrons to react with lithium, and then recover tritium, so that tritium becomes similar to the existence of catalysts.

However, the current tritium consumption/proliferation ratio is very low (1:1.05 in memory, which may be wrong), so the tritium dissipation at all stages must be strictly controlled. Among them, because the first wall is in direct contact with the plasma, it is regarded as a large tritium retention and needs to be strictly controlled. Otherwise, the more tritium is used, the less it will be, which will directly lead to the extinguishment of the plasma and the shutdown of the reactor.

The second is the ability to resist neutron irradiation.

Each deuterium-tritium fusion produces a 14 meV neutron that can easily break the metal bonds in the first wall of the material, resulting in a large number of defects that cause irradiation swelling, embrittlement, creep and other problems, making the material completely unusable.

The first wall neutron dose is expected to exceed 100 dPa during the commercial fusion reactor service period, while the fission reactor dose is in the order of 1 dPa, so it is not possible for existing fission reactor material to be used directly in fusion reactors.

Third, resistance to plasma irradiation.

At present, the boundary of magnetic confinement is not ideal, and there is still a lot of room for improvement in plasma turbulence control.

As a result, the first wall, especially the deflector armor, is still subjected to high-flux deuterium/tritium/helium plasma impacts. When these plasmas blast into the material, they accumulate on the surface, causing the surface to blister and fall off.

On the one hand, the surface integrity of the material is destroyed, and on the other hand, the debris that falls off into the plasma will also cause the plasma to burst.

Fourth, the problem of low activation.

Under neutron bombardment, many elements undergo nuclear reactions and transmute into other nuclides. Some nuclides are unstable and decay further to continue to emit radiation. In this way, the fusion reaction has no advantage of being free of radioactive contamination products, so the materials used as the first wall are low-activation materials, that is, elements that remain stable and do not decay after transmutation.

For example, at first, people planned to use molybdenum metal as the first wall material, but later found that the transmutation products were too difficult to deal with due to radiation, and now they are gradually replacing it with tungsten metal.

Fifth, high temperature resistance and thermal shock resistance.

The working temperature of the first wall of the commercial fusion reactor is above 1000, and the moment the plasma bursts can reach 2000~3000, and low-melting materials such as steel and copper are directly eliminated.

In addition, the task of the first wall is to export the heat energy, and ceramic materials with high melting points but poor thermal conductivity are basically eliminated.

At present, the melting point of tungsten metal, a promising candidate material, is 3400. However, tungsten also has the disadvantage of poor plasticity, and the thermal stress often causes the surface of the material to crack under the thermal shock of ion bursting.

It is already very difficult to meet one of the above conditions, and the material that meets all the conditions does not currently exist.

Because of this, controlled nuclear fusion is considered to be the most challenging mega-scientific project in the history of human science and technology.

But for Pang Xuelin, none of this is a problem.

In the world of the Wandering Earth, human beings have already achieved heavy nuclear fusion technology, and light nuclear fusion is certainly not a problem.

Back then, in the Wandering Earth World, Pang Xuelin also specially memorized the technical route of controllable nuclear fusion.

Although he did not go into detail about the specific technical details, he was well aware of the key nodes and technical directions for achieving controlled nuclear fusion.

He originally thought that when he returned to the real world, he might be able to use it.

But he soon realized that in the real world, he simply couldn't take the lead in controlled fusion development.

And even if he knows the direction of technological development, with the level of real-world scientific and technological development, if he wants to actually build a fusion reactor that can be operated commercially, the cycle will be at least ten years or more.

So in the real world, he prioritizes making breakthroughs in the field of carbon-based chips and high-density energy storage batteries, and will only get controlled nuclear fusion out when he has the opportunity in the future.

But in the three-body world, none of this is a problem.

Even, Pang Xuelin has to deliberately control the realization time of controlled nuclear fusion, and he must come up with controllable nuclear fusion after the arrival of the great trough, when the power of various countries has weakened to the point where they are unable to control the global situation, so as to maximize the benefits.