Start sweeping the universe by rubbing the CPU with your hands.

Chapter 366 Sky Eye No.

Primordial gravitational waves refer to the early period of the Big Bang, as early as about 10^-36 seconds to 10^-32 seconds after the birth of the universe. During this extremely short period of time, the universe experienced a period of extremely rapid inflation.

During this process, the universe as a whole exploded at a speed many times faster than the speed of light. Of course, this was only an explosion at the spatial level and not a super-light movement of matter, so it did not violate the existing theory.

At this stage, the gravitational waves released by the super-light explosion of the universe are called primordial gravitational waves.

Primordial gravitational waves have special significance. Through a certain complex mechanism, existing theories can treat the existence of primordial gravitational waves and the existence of gravitons as the same issue.

In other words, there is no need to directly observe gravitons. As long as the existence of original gravitational waves can be confirmed, the existence of gravitons can be confirmed.

So now, the question becomes, how to confirm whether primordial gravitational waves really exist?

Fortunately, this problem can be solved through observation, but it is more difficult.

Because the wavelength of the original gravitational wave is too long and the frequency is too low. Its wavelength is even long enough to be equivalent to that of the observable universe, that is, it has a wavelength of tens of billions of light-years.

As early as the first-level civilization stage, humans have confirmed the existence of gravitational waves and actually detected gravitational waves.

However, the gravitational waves detected by early humans have extremely high energy, extremely high frequency, and extremely short wavelength. They are usually violent physical processes such as black hole mergers, black holes devouring neutron stars, and neutron star collisions.

For example, the merger of double black holes has been detected.

The LIGO detector originally used to detect this gravitational wave radiation event observed a length change of less than one ten thousandth of the diameter of a proton due to this gravitational wave, thus confirming the existence of this gravitational wave.

Faced with this kind of gravitational wave, humans who have developed to the pinnacle of level three civilization and already have many means of detecting gravitational waves cannot detect it.

A pulsar is a type of neutron star. It emits extremely strong radiation and its rotation is extremely stable.

People regard pulsars as the laser base of laser array interferometers to detect the existence of gravitational waves.

Where did the missing 3 times the mass of the sun go?

The answer is that it radiates to the entire universe in the form of gravitational waves.

The principle is simple. The radiation interval of pulsars is extremely stable. If gravitational waves pass through, the radiation interval of the pulsar will change extremely slightly. By measuring this change, you can measure the properties of gravitational waves.

For such an intense gravitational wave radiation event, the frequency of the gravitational wave is about 250HZ, which means it vibrates 250 times per second.

But the final result after the merger was only about 62 times the mass of the sun.

The transmission speed of gravitational waves is the speed of light, so the wavelength of this gravitational wave radiation is about 1200 kilometers.

By this method, the distance between the Earth and the pulsar used as a clock can be equivalent to the arm length of the gravitational wave detector.

However, humans also have a gravitational wave detection method with higher detection accuracy, the pulsar timing array detector.

At this stage, humans have built laser bases tens of millions of kilometers apart in the galaxy.

In simple calculation, the mass of the large black hole after the merger should be the sum of the masses of the two small black holes before the merger, which is 65 times the mass of the sun.

The electromagnetic waves emitted by the rapidly rotating pulsar will sweep across the earth at a fixed frequency like the light of a lighthouse.

At this moment, the gravitational wave radiation power of the merger of the two black holes was as high as 3.6*10^49 watts, and its instantaneous power was even 10 times greater than the power of all visible light radiation in the entire observable universe.

For gravitational wave detectors, it can be simply thought that the longer the detector's arm length, the higher the detection accuracy.

As a result, mankind has reached the point where the arm length of gravitational wave detectors has been upgraded to hundreds or even thousands of light years.

The laser gravitational wave detectors built in interstellar space and separated by tens of millions of kilometers are equivalent to arm lengths of tens of millions of kilometers - for comparison, the arm length of the detector that originally detected the gravitational waves of the black hole merger was 4 kilometers - no primordial gravitational waves can be detected.

However, gravitational waves with a wavelength as short as 1200 kilometers are already so difficult to detect. So, how can we observe the original gravitational waves whose wavelength is equivalent to that of the entire observable universe, that is, about 960 billion light-years? ?

About 13 billion light-years away from the solar system, a black hole with a mass of 36 times the mass of the sun and a black hole with a mass of about 29 times the mass of the sun revolved crazily around each other, and eventually merged to form a large black hole .

From the initial arm length of 4 kilometers, to the arm length of tens of millions of kilometers, and now the arm length of thousands of light-years, humankind's ability to detect gravitational waves has achieved a huge leap, and the detection accuracy has improved by more than a thousand. hundred times.

But...it's a pity that even if the detection accuracy has improved so much, there is still nothing we can do to face monsters like primordial gravitational waves whose wavelength reaches the diameter of the observable universe.

To detect primordial gravitational waves, we need to find another way and a completely new detection method.

Han Yang found a theoretical method to detect primordial gravitational waves.

Because the universe exploded at super-light speed in the early days of the Big Bang, and the original gravitational wave could only be transmitted at the speed of light, it was "sealed" in the cosmic microwave background radiation.

The cosmic microwave background radiation can be simply regarded as the first ray of light since the birth of the universe, and can be called the "primordial light".

It is a type of electromagnetic radiation that fills the entire observable universe and has a temperature of approximately 2.725 degrees Kelvin.

If primordial gravitational waves exist, they must have become part of the cosmic background radiation.

However, everything that exists must leave traces. Through sociological means rather than scientific means, Han Yang already knows that primordial gravitational waves do exist, so such traces must also exist.

From this, Han Yang found the ultimate means to complete the quantization of gravitons: through the detection of the cosmic microwave background radiation, find the impact of the original gravitational wave and separate it.

This is also an extremely difficult thing. After all, even if such an impact does exist, it must be extremely small. To detect it, one must have detection equipment and methods with almost incredible sensitivity.

However, even if this is extremely difficult, it is possible to achieve it after all, unlike other methods, such as direct observation of gravitons and observation of original gravitational waves through gravitational wave detectors, which are simply impossible to achieve. After completing the digestion and absorption of all the scientific data purchased from Yunguang Civilization, Han Yang confirmed that at this moment, he had the theoretical possibility of manufacturing observation equipment with high enough accuracy.

Of course, this is just in theory. It is still extremely difficult to turn theory into practice and actually build such detection equipment.

In other words, simply manufacturing this kind of detection equipment is actually not difficult - for a human civilization that already has such powerful engineering power, it is possible to push a planet. What kind of equipment can hardly accommodate humans?

To be more precise, how to build this kind of equipment is the most difficult thing.

This involves a lot of theoretical calculations.

People must first determine what parameters are needed to have the possibility of detecting this effect, and then study how to achieve this parameter, what kind of materials and structures should be used, and so on.

Based on this goal, the human scientific community and Han Yang simultaneously carried out a large number of calculations and research, and carried out experiments again and again.

During this process, countless extremely difficult scientific questions emerged. Although Roche analysis, a powerful mathematical tool, has greatly improved efficiency and reduced difficulty, the human scientific community still shows signs of insufficiency.

There is no way. Over the past hundreds of years, they have become accustomed to an environment of learning existing knowledge and then doing micro-innovation and applied research based on the existing knowledge. Now I have to explore the unknown territory by myself - there is no way, I really don't have the thinking and consciousness.

Han Yang knew that scientific research talents who truly possess this kind of scientific thinking and awareness can only be slowly cultivated from the next generation.

Generally speaking, ordinary civilization will not have this opportunity. Because the internal and external environment does not allow it.

Only humans who have their own existence have this opportunity.

The human scientific community can only do some auxiliary work, and the key core of this work falls on Han Yang.

Fortunately, Han Yang at this stage has gone through several major upgrades before and has enough confidence to face this problem.

During this process, Han Yang first confirmed the external environment required to build such detection equipment.

The lower the various interference radiations, the better.

This environment is different from neutrino detectors that require extremely low background radiation. Neutrino detectors can be built extremely deep underground, shielding them from almost all external radiation. But if this kind of detection equipment is built underground, even the cosmic microwave background radiation will be shielded, so why is it detecting?

Other types of radiation must be as low as possible without affecting the cosmic microwave background radiation.

The only places that meet this kind of detection conditions are far away from stars and other celestial bodies.

The reason is simple. Stars are the most numerous and widespread sources of strong radiation in the universe.

In addition to stars, other stars with strong radiation will not work. Black holes, neutron stars, white dwarfs, especially such extreme stars that are in the process of accretion, should be kept as far away as possible.

Han Yang finally picked a place about 16.2 light-years away from the solar system.

There, the nearest star is 5 light-years away. And the surrounding stars are all red dwarfs and yellow dwarfs with low radiation power, and there are no supermassive stars such as blue giants.

After the address is selected, the next step is to combine the specific local environment and make a detector structure that can better adapt to the local environment.

Of course, before that, Han Yang had to confirm what standards the detector needed to meet.

Combining existing scientific data, that is, although I don’t know what detection standards can detect this effect, I already know which detection standards cannot detect this effect.

This confirms the performance lower limit.

Through a large number of calculations and solving a series of extremely complex equations - mathematical tools such as Roche analysis played an important role in this. Many complex equations that could not be solved before were applied by this new mathematical tool. , one after another asked for the answer.

Of course, this process cannot rely solely on Han Yang’s own computing power. It's not that Han Yang can't figure it out himself, but it's just too wasteful.

For this kind of calculation, just write a program and leave it to a specialized supercomputer to do it, without wasting your own computing power.

As a result, Han Yang selected a dwarf planet located at the edge of a distant galaxy, about 2000 billion kilometers away from the sun, and started building a large-scale supercomputing center there.

A major indicator that restricts supercomputing performance is heat dissipation. Because this dwarf planet is far away from the sun, its surface temperature is as low as minus 260 degrees Celsius, which just meets the heat emission of supercomputer.

On this dwarf planet, Han Yang mobilized human engineering capabilities, coupled with his own engineering capabilities, to build tens of thousands of supercomputing centers in just a few years, each of which Although his computing power is not as good as Han Yang's own, it is still limited.

These tens of thousands of supercomputing centers were operating at full power and began to calculate one after another complex calculation problems submitted by Han Yang and the human scientific community. The heat released by them even caused the surface of the dwarf planet to drop directly from minus 260 degrees The temperature has increased to a level of two or three degrees above zero, melting all kinds of solid gases on the surface of the planet, such as dry ice, methane, solid hydrogen and oxygen, etc., directly giving the dwarf planet a thin atmosphere.

Fortunately, with the atmosphere, the planet radiates more heat energy outwards, barely reaching a balance between heat production and heat release. The temperature of the planet does not increase any more, so supercomputers can continue to operate on this planet.

After all-out calculations and verification, a series of extremely precious scientific data output finally allowed Han Yang to slowly form the basic concept of this detector in his mind, and initially figured out how to build it, and What performance indicators should be achieved.

After clarifying this point, the fifth-level civilized space carrier was specially transferred back, and the hundreds of millions of tons of materials transported to the construction site can begin to be used.

After two years, the giant cosmic microwave background radiation detector named "Tianyan-1" by Han Yang was finally completed.

In the vast universe, reflected by thousands of stars, one side of this giant detector is like a smooth mirror, completely reflecting the appearance of the universe.

Behind its smooth mirror surface are devices one after another. Different devices are connected by various pipes and complex cables. There are hundreds of thousands of large and small devices.

The cross-sectional area of ​​this detector is a full 4.6 square kilometers.

(End of this chapter)