Hundreds of years ago, mankind finally entered the road of technological development and ushered in a stage of brilliant and rapid development. With the help of science and technology, we have astronomical telescopes, wireless signal transmission equipment, and rocket ships that can get out of the earth.
The continuous emergence of newer technologies has brought huge benefits to people’s lives and promoted the faster development of human civilization. But when we walked out of the earth and saw the vast universe, a problem that we had to face and think about appeared, and that was alien civilization.
In the early days, human beings were more of a kind of curiosity when they explored and found alien civilizations. They wanted to know what the alien civilization looked like. How are they different from human civilization? However, with the continuous advancement of human science and technology and the continuous improvement of the cognition of the universe, the attitude towards searching for extraterrestrial civilization is constantly changing, from the original fierce madness to the constant turning to caution.
Why has the attitude of scientists to alien civilizations changed so much? The reason is that although we have not yet discovered any alien civilization, from the perspective of the cosmic scale, the probability of the existence of alien civilization is basically 100%, and now astronomers have no doubt about the existence of alien civilization.
If alien civilizations exist, we have to consider whether they are friendly to mankind? We must know that real peace cannot be maintained within human beings. From ancient times to the present, there have been many wars. Alien civilization and human beings are completely different life types. We look at aliens as if they are looking at monsters. They may look very ugly and strange to humans.
The same is true for aliens looking at humans, unless the appearance of aliens is very similar to that of humans, in which case it is possible for both parties to maintain a certain degree of friendliness. However, from the perspective of life evolution, the possibility that alien intelligent life forms are very similar to humans is very small. Therefore, it may be more difficult for alien civilizations to maintain a friendly situation with humans, especially alien civilizations. The strength is much higher than that of human beings.
At this time, we thought of the “Black Forest Law” proposed by scientists. This law tells us that the entire universe is a quiet forest, in which the intelligent civilization hides itself for fear of being discovered by other civilizations. Once the two civilizations meet, there is a high probability that a civilization war will break out, and one side will completely end the other.
With the continuous improvement of human cognition of the universe, scientists increasingly believe in the existence of the “Black Forest Law” of the universe, so our attitude towards alien civilizations is now much more cautious than in the past. Even so, some people think that the location of the earth may have been exposed. The reason for saying this is because of various crazy actions of scientists in the past.
We must know the big explosion of human science and technology in the last century. With advanced technology, we can initially explore the universe. Scientists have carried out various plans and missions in order to find alien civilizations. For example, Voyager 1 and Voyager 2 launched in 1977, both of which carry a CD containing information about the earth and human beings.
If this disc is obtained by an alien civilization, then the existence of human beings and the coordinates of the earth will be exposed. This is a very crazy move by scientists, and it is also an act that humans lack more knowledge of the universe soon after they have just walked out of the earth. I believe that we will never do such a thing now. Even if we launch a probe to the edge of the solar system, we will only put a piece of information on the earth and mankind on it.
Fortunately, the range of the solar system is much larger than what scientists thought in the past. According to the current observation data, the Oort Nebula is the outermost part of the solar system. If this is the case, the diameter of the solar system has reached more than 2 light-years, and it would take at least tens of thousands of years to pass through at the speed of Voyager. Therefore, we don’t have to worry about the existence of the earth being exposed by the disc on the Voyager.
And our concern about the possible exposure of the earth’s location does not refer to the Voyager, but to radio signals. No matter how fast the Voyager is, it is far from comparable to the speed of radio waves. The speed of radio waves has reached the speed of light, and it can go out for a light-year in a year.
The first radio signal in human history began in 1901, and it has been 119 years since then. If this signal can always exist and spread, it should now be 119 light years away from the earth. After the emergence of radio signals, various radio signals have actually been continuously spreading from the earth to the universe.
According to the propagation speed of the speed of light of the radio signal, the range now composed of the earth as the center and the end of the radio signal in 1901 is approximately a sphere with a diameter of 119 light years. Within this range, the continuous radio signals sent by humans are flooded with it. If there is a scientific and technological civilization like humans in this range, it is possible to receive signals from the earth.
Of course, the above radio signal range is only a theoretical value. In fact, most of the various signals sent by humans are attenuated when they pass through the atmosphere. Even if they can get out of the earth, they will be weak at most from the solar system. Too unable to receive and distinguish. Therefore, we don’t have to worry about the various radio signals emitted by human beings in daily life spread to the far depths of the universe.
Human signals that are really likely to spread to very far away are those powerful broadcast signals. Such signals have higher energy levels, greater strength, and can travel far away. Under normal circumstances, as long as humans do not actively send high-intensity radio signals to the depths of the universe, the possibility of the earth being discovered by alien civilizations through signals is basically zero.
But the cruel reality is that in the past 100 years, in order to explore and find possible alien civilizations, scientists have sent strong wireless signals to the depths of the universe many times. For example, in 1974, they created the “Drake formula”. “The astronomer Frank Drake, with the help of Carl Sagan and many other scientists, compiled information such as the position of the earth, the composition of human DNA, and the world population into a code, and transmitted it to M13, which is 22,200 light-years away from the earth. cluster.
Many people may say that the M13 star cluster is 22,000 light-years away from the earth. Even if human radio signals can be transmitted here, it will take 22,000 years. In such a long period of time, human civilization can develop to a very high level. At that time, even if the earth is known by alien civilizations, we don’t have to worry at all.
So can this strong directional signal really only be received by the possible alien civilization of the M13 star cluster in 22,000 years? the answer is negative. If there are many interstellar civilizations in the Milky Way that are stronger than human beings, then these interstellar civilizations have a very wide range of activities. In the 22,000-light-year interstellar space between the Earth and the M13 star cluster, there may be other areas of high-level civilization activity.
The signal sent by the scientist may not have reached the M13 star cluster, but was received by other interstellar civilizations halfway through. In this way, the existence of the earth and humans is also exposed. Therefore, after this strong wireless signal is sent out, the future of mankind will be full of various risks. Maybe now this signal has been discovered by interstellar civilizations halfway, and they may already know the earth. And human existence.
This shows that it is actually a wrong way for humans to actively send strong wireless signals into the universe. We don’t know where and in which direction the advanced civilization of the universe is, and we also don’t know whether the law of the dark forest of the universe exists. If this law exists, then this kind of active exposure of human beings is very dangerous.
Hawking has repeatedly issued warnings, telling humans not to actively search for alien civilizations, let alone reply to any alien civilization signals. This shows that Hawking also very much recognizes the law of the dark forest. In his opinion, alien civilizations may not be friendly. When they discover a low-level civilization like humans, the most likely thing is to colonize the earth and enslave humans.
As long as human beings hide and develop quietly, it is the best policy to wait until our strength becomes truly powerful and becomes an interstellar civilization. We then take the initiative to go out of the solar system to explore and find alien civilizations, and to contact and communicate with alien civilizations.