cosmic hegemony

Chapter 256, Quantum Communication
"The surrounding gravitational force is normal, and it can be determined that it is definitely not a black hole, and it must be the entrance and exit of space-time ocean currents."

As if he had discovered something new, Chen Bin began to study it carefully. If it was a black hole, with the huge mass of the black hole, the surrounding gravitational force would be abnormal. It can be easily found through the gravitational mirror, but there is no abnormality now. , indicating that it is not gravity.

"Launch a small spaceship into it."

The hatch of the huge elliptical flying saucer-shaped spaceship slowly opened, and a small unmanned spaceship flew out slowly. It was driven by plasma power, and it dragged a long, white and dazzling tail flame towards the The entrance and exit of the space-time ocean current flew away, like a firefly in the dark void, very clear.

As soon as the unmanned spaceship entered the range of the entrance of the space-time ocean, it disappeared almost instantly, as if it was completely swallowed by the surrounding darkness.

"Lost contact, no radio contact."

"Well, it seems that it entered the space-time ocean current, the speed of flying in the space-time ocean current exceeds the speed of light, and it should be able to shield electromagnetic waves. Only after it leaves the space-time ocean current and reaches the Centaurus galaxy can it contact us again. It’s just that the Centaurus galaxy is 4.3 light-years away from us, and it will take several years at the speed of electromagnetic waves.”

Chen Bin nodded. Now he is sure that this is the entrance and exit of the space-time ocean current. Through this space-time ocean current, he can reach another galaxy in a very short time.

"Haha, brothers, I have discovered space-time ocean currents here."

In the virtual chat world, Chen Bin happily shared the good news, but others would not receive it for a while. The solar system is insignificant compared to the vast universe, but it is still very vast, even at the speed of electromagnetic waves. It will take several hours to get in touch with the earth from here, and the time will be multiplied by 2.
It can be said that the vast void of the universe is not only restricted by transportation technology, but also by communication technology. Even if the speed of electromagnetic waves reaches the speed of light, it still seems too slow in the radiant void of the universe.

A few hours later, Li Fu finally received a message from Chen Bin on Earth dozens of astronomical units away.

"Yu Liang, Tang Boyuan, Dong Zhifei, Luo Xiaoyao, Zhan Fei, Chen Bin has already discovered space-time ocean currents, have you gained anything?"

Li Fu started to contact people from several other directions. In the star system closest to the solar system, basically every direction sent a spaceship to explore.

"We have also discovered the space-time ocean current in the direction of the Canis Minor galaxy 11 light-years away from the solar system."

This is Yu Liang's reply.

"The space-time ocean current in the direction of Aquila has also been discovered, and it is currently undergoing precise positioning."

Tang Boyuan also gained something here, the Aquila galaxy is 16 light-years away from the solar system.

"No space-time ocean current has been found in the direction of the Antarctica galaxy, and it is still being detected."

Luo Xiaoyao had nothing to gain here, the Antarctica galaxy is 22 light-years away from the solar system.

"There is no space-time ocean current in the Antarctica galaxy 22 light-years away. If it is said, there will be no time-space-ocean current connection if the distance is more than 20 light-years away?"

While collecting everyone's data, Li Fu carefully analyzed the data.

"Luo Xiaoyao, Zhan Fei, Dong Zhifei, you guys should search here for a few more days. If you don't find anything, it means that there may be no space-time ocean currents beyond the distance, and you can return to Earth."

It’s just a few pieces of information, and it’s been several days since they came back and forth, because the distance is too far, with a distance of dozens of astronomical units, it takes more than ten hours for the electromagnetic signal to go back and forth. It is really difficult for people who are used to real-time communication now.

"It seems that it is necessary to develop quantum communication technology. In the solar system, communication has been delayed to this point. If you go to other galaxies in the future to contact the solar system, if you still rely on the current communication technology, let's not talk about it." Whether you can get in touch or not, the time alone is calculated in years."

"Even for the nearest Centaurus galaxy, which is 4.3 light-years away from the solar system, it takes 8.6 years for this electromagnetic wave to come and go. Such a long time, the day lily has bloomed and withered many times."

Li Fu began to think about it. Communication technology and transportation technology are two things that really restrict human footsteps. Just like in ancient times, it is impossible to rule the entire earth by riding horses and communicating with carrier pigeons. Mongolia had a vast territory back then. The empire fell suddenly, in fact, it was not because the territory was too vast, and the central government simply had no power to deal with the outlying areas. Under certain conditions, such a vast territory would only be short-lived.

Only in modern times, with the rapid development of transportation technology and communication technology, let alone a territory as large as the Mongolian Empire, even if the entire earth is brought under the rule of one country, there is no problem at all, because powerful transportation technology, advanced Advanced communication technology is enough to allow the ruler to mobilize support from all over the world to any corner in a short period of time.

But in the interstellar era, the universe is even more vast, even at the speed of light, it is very slow. Only in the solar system, the communication of electromagnetic waves seems to be unable to keep up with the requirements of the times.

The quantum communication technology mentioned by Li Fu is the next generation of advanced communication technology proposed by scientists. The principle of quantum communication technology is a technology based on the principle of quantum entanglement effect.

Quantum communication is mainly based on the theory of quantum entanglement, using quantum teleportation (transmission) to achieve information transmission.According to experimental verification, no matter how far apart two particles are in an entangled state, as long as one changes, the other will also change instantaneously.

The process of using this characteristic to realize quantum communication is as follows. A pair of particles with entangled state is constructed in advance, and the two particles are placed on the two sides of the communication respectively, and the particle with unknown quantum state and the particle of the sender are jointly measured (an operation) , then the receiver’s particle collapses (changes) instantly, and the collapse (change) becomes a certain state, which is symmetrical to the state of the sender’s particle after the collapse (change), and then the joint measurement information is transmitted through the classical channel For the receiving party, the receiving party performs unitary transformation (equivalent to inverse transformation) on the collapsed particles according to the received information, and then the unknown quantum state exactly the same as that of the sending party can be obtained.

To put it simple and easy to understand, that’s it. Quantum is like a pair of twin brothers, and the twin brothers are copies of each other. If one raises his right hand, the other will also raise his right hand. When one laughs, the other will laugh too, that is, no matter what action one of them makes, the other will also make the same action.

And no matter how far apart the two brothers are, the actions of the two brothers will always be the same in any state, and there will be no time difference between them, and there will be no difference because of the distance. This is quantum entanglement state.

Because of this characteristic of quantum entanglement, the power of quantum communication technology has emerged as the times require. In theory, quantum communication technology can ignore distance. No matter how far away it is, quantum communication technology can realize real-time communication. any delay.

No matter the distance communication technology, this is definitely the technology that must be mastered for space travel and interstellar colonization. No matter how far the distance is, one can keep in touch anytime and anywhere, and there will be no communication delay due to the distance.

In addition to ignoring the specificity of contacting at any time regardless of distance, quantum communication technology has several other characteristics that scientists are full of praise, one of which is security.

Compared with traditional communication technology and quantum communication, its security and efficiency cannot be compared with it.In terms of security, quantum communication will never "leak secrets". One of them is that the key of quantum encryption is random. Even if it is intercepted by the thief, the correct key cannot be obtained, so the information cannot be cracked.

Second, there are two entangled particles in the hands of both communication parties. If the quantum state of one particle changes, the quantum state of the other party will immediately change accordingly. According to quantum theory, any observation and interference at the macro level will be Immediately change the quantum state, causing it to collapse, so the information obtained by the thief due to interference has been destroyed, not the original information.

In addition, quantum communication is very efficient. The transmitted unknown quantum state will be in an entangled state before being measured, that is, it can represent multiple states at the same time. For example, a quantum state can represent two numbers of 0 and 1 at the same time. Seven such quantum states The state can represent 7 states or 128 numbers at the same time, that is, 128~0.Such a transmission of optical quantum communication is equivalent to 127 times of traditional communication. It is conceivable that if the transmission bandwidth is 128 bits or higher, the difference in efficiency will be astonishing.

Of course, many people may not be able to understand quantum entanglement. Quantum entanglement can be understood with the help of "Schrödinger's cat": when a cat is put in a box containing poison, and then the box is closed, after a while, ask the cat what is it now? dead, or alive?
The answer of quantum physics is: it is both dead and alive.Some people will say that you will know if you open the box and look at it. Yes, you will know whether the cat is dead or alive when you open the box, but according to the interpretation of quantum physics: this state of dead or alive is the result of artificial observation, that is, Human’s macroscopic interference makes the cat become dead or alive, which is not the real state when the box is covered. Similarly, the microscopic particles are always in the two states of “dead” and “alive” before being “disturbed” It can also be said that it is both "0" and "1", so the security guarantee of quantum communication technology is very reliable.

Because of the characteristics of quantum entanglement, even if you intercept the information, because of the characteristics of entanglement, when you artificially crack the information macroscopically, the quantum state will be changed immediately, causing it to collapse. Therefore, the information obtained by the thief due to interference has been Destruction is not the original information.

The three characteristics of real-time, security, and high efficiency of quantum communication technology are not available in traditional communication technology.

PS: Ask for tickets, all kinds of requests!
(End of this chapter)