Chapter 138 Gravitational waves
"I don't lack money. I have money. If I don't bring it to life and die, I won't take it away. What I spend is money..."
When he walked out of the nuclear fusion laboratory, Lu Yi kept muttering that he signed a name on a financial expenditure statement that Xu Ying had just received, and then spent 3 billion US dollars.
This money is loaned to the Tomorrow Group and the bank. Although the bank will not pursue the "unprofessional" of this money, there is no doubt that Tomorrow Group has negative assets of more than US$20 billion now.
If it weren't for the upcoming cancer suppression drug to be supported, if it weren't for the continuous profit dividends brought by superconducting graphene wires and controlled nuclear fusion, he wouldn't be the richest scientist in the world, but the most negative scientist.
If the billions of dollars spent to buy a hen that lays golden eggs, it would be acceptable to spend it, just like the mold of superconducting graphene wires.
But now I spent it to buy a bunch of metal hydrogen, which is only enough for a small nuclear fusion reactor and a spacecraft space engine. It doesn’t work if you want more, it is a consumable material.
Even he felt a sincere waste. When he saw his signature, Xu Ying looked at the look of awesome boss, you are stupid and you are rich.
"In this way, the cost of small fusion reactors and aerospace engines will reach US$3.2 billion. Including the design and production and construction of other equipment and instruments of the spacecraft, the entire spacecraft will be as high as US$6 billion.
This is because we are familiar with the country, and we have many technologies, equipment, equipment, and aerospace industry to give discounted prices."
Lu Yi roughly calculated the account and said with a little stuttering and painful words: "Sure enough, gravitational waves are not something that cannot be played by rich players. This is just a vehicle for equipment and instruments. The cost of laser interferometer has not been calculated yet. The spacecraft maintenance cost during the multiple delivery of equipment to the sky will be carried out. Cooperate with the country or further improve the cost of the spacecraft to be manned to the sky to assemble laser interferometer.
If the research fails, almost 10 billion US dollars of funds will be wasted.”
He and Zhang Qing were preparing to study space gravitational waves and thought about ground research, so that they could look decent if they spent hundreds of millions of dollars.
However, after consulting a large amount of literature, it was determined that the ground research was limited by the interference of environmental noise, and the limit of the research could only stop at the "discovery" of gravitational waves. If you want to study more subtle frequency fluctuations and deeper information of gravitational waves, the difficulty would be exponentially increased.
This is the same as when you can't hear the whispers of people 10 meters away in the nightclub where DJ music is so lively. Compared to the relatively quiet environment in space, the ground is in ambient noise.
"I hope there is good news for the ligo project tomorrow."
Looking forward, Lu Yi took out his notebook to check the data obtained from Tianqin's plan to da Qiufeng.
He and Zhang Qing are both just starting out in the research on space gravitational waves. Even if they have systematic assistance, but lack relevant equipment and instruments without actual verification, the progress is also unsatisfactory.
This is why Zhang Qing was so happy to hear that the US NSF agreed to provide the relevant parameter data of the Ligo Observatory and the complete data of the last time Ligo discovered gravitational waves. She really has too many guesses and ideas in her mind and needs to be verified through actual experimental data to determine.
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"Outside ambient noise comes from the environment, it can come from a slight fluctuation of the Earth's shock wave under your feet, a fluctuation from the sun or other planets, or even from the equipment and instruments themselves.
From this perspective, environmental noise problems are inevitable.
What we want to ask is, when encountering interference from external environmental noise, how should we identify which experimental data are useful and which are interference data caused by noise? What solutions are used for this problem?”
During the video conference with the Ligo project team the next day, Zhang Qing raised a question that Principal Luo asked for help from Tianqin Project. At the same time, this question also troubled Lu Yi's problem.
The essence of gravity is the bending of space and time, while the essence of gravitational waves is the ripples of space and time.
Although matter is gravity, it will cause ripples when gravity is produced, just like the ripples on the lake surface caused by throwing a stone in a calm lake.
But gravitational waves are too small. They are as small as exceeding the detection limits of conventional human means, as small as the fluctuations of the equipment themselves can cause serious interference, or even as small as beyond the limits of ordinary people's imagination.
Gravitational wave intensity = (40*million gravitational constant*moment of inertia*square*elusivity of frequency)/(4th power of light*distance)
The unit symbol of the gravitational constant is G, G=0.00000000000667.
The speed of light is used as the unit in this formula, which means c=300000000.
From this formula, from the calculation process of multiplying G first and then dividing the fourth power of the speed of light c, you can clearly feel how gravitational waves are small.
Take the famous Crab Nebula Nebula as an example. It is 6,500 light years away from us and rotates 30.3 times per second. We feel that its gravitational wave intensity changes on Earth are 1e-23 meters.
What is this concept?
The radius of the smallest atom hydrogen atom: 1e-10 meters.
This is equivalent to seeing the gravitational waves of the neutron star in the Crab Nebula, we must open our eyes and see clearly the changes in a hydrogen atom 1 billion kilometers away.
What are high-precision machine tools, what are nanometers, and what are single-atom layers, and they are all slag in front of gravitational waves.
It is conceivable how unparalleled the shock and excitement of the heart when a person who understands this concept learns that the gravitational wave has been determined to be successfully detected.
The miracles created by humans have exceeded their imagination!
“For noise, this involves a precision issue.”
The scientists from the ligo project team heard Zhang Qing’s question and thought about it: “On the one hand, we need to improve the noise in the external environment as much as possible and improve the stability of the instrument, and at the same time, we can adopt another method.
We arrange high-precision instruments around the space of the gravitational wave observatory. The noise from the outside will be first felt by these high-precision instruments before affecting the detection.
By calculating the attenuation of these noises, it can be derived from the data changes when it affects doping into the actual detection. Finally, when the detection test is completed, we cancel this part of the noise data in the collected test data."
"We cannot be 100% sure that the part of the data that is offset and discarded is completely noise data, which will cause the missing part of the valid data."
Zhang Qing immediately realized the shortcomings of this method and asked a rhetorical question while recording it in her notebook.
"This is a problem. Compared to the actual interference caused by environmental noise, this solution is that the benefits outweigh the disadvantages."
The scientists from the ligo project team shook their head helplessly and said, "Of course, we also need to improve the stability and precision of the instrument as much as possible and reduce environmental noise. This is the best way to solve the root cause problems.
In addition, we need to arrange multiple gravitational wave observatories at different spatial locations and spatial distances. Through the data detected by two or more observatories, everyone can verify each other further and further solve this problem and determine the accuracy of the data."
"I heard that you are planning to arrange a large laser interference gravitational wave observatory in space. We can actually cooperate in this regard."
This was another scientist from the ligo project team who spoke, and said with some expectation: "One is on the ground and the other is in space. Everyone's detection data can verify each other, which can better help the development of gravitational wave research."
"This matter will be discussed later. After all, our spacecraft are all on the drawings, and our laser interference observatory has not yet come out in the factory."
Faced with this requirement, Lu Yi, who had just used the system to assist in understanding the experimental data sent by Ligo, smiled and exposed the topic. Then he marked several lines of data with a laptop to display it in the video screen. He looked at the scientists of the Ligo project team on the big screen and asked:
"When I was just looking at your test data, I found several rows of unusual fluctuations, which flashed and were incomplete.
Chapter completed!