The search for extraterrestrial intelligence - or, as it is now accepted to abbreviate this activity by its English abbreviation, SETI (Search for Extraterrestrial Intelligence) - was first put on the agenda of modern science at a conference at the radio observatory in Green Bank (Green Bank). West Virginia, USA, in 1961
It was noted that, having received powerful radio telescopes at their disposal, scientists can now start tracking signals sent in our direction by extraterrestrial civilizations from outside the solar system (provided that such civilizations exist and seek to establish contact). In those optimistic early days, SETI enthusiasts assumed that there were thousands upon thousands of civilizations in the Universe united in "galactic clubs" and that we were on the verge of joining such an interstellar community in our Galaxy.
Perhaps they would have shown great restraint if they had heeded the opinion expressed eleven years earlier by the American physicist of Italian origin, the Nobel laureate Enrico Fermi. Once at lunch in Los Alamos, after listening to the arguments of his colleagues in favor of the existence of a great number of highly developed technological civilizations in the Galaxy, after a pause, he simply asked: "Well, where are they then?"
Since then, this argument, formulated in one way or another, has been the main fork in the side of the SETI community. I will give an example of one of its detailed formulations: “The laws of nature are the same throughout the Universe, therefore any highly developed civilization has the same scientific, technical and technological capabilities as humanity. We already have quite real projects of interstellar spacecraft capable of reaching speeds of about 10% of the speed of light, and such ships in the foreseeable future may well deliver people to the nearest stars. Any civilization with such ships could settle throughout the galaxy and colonize habitable planets in just a few million years - a huge time from the point of view of human history, but on the cosmic scale it is just a moment.
If there really were thousands of civilizations in the Galaxy today, the first of them would have arrived here millions of years ago. Michael H. Hart (b. 1932) in 1975 put forward the argument that the very absence of aliens on Earth right now is convincing evidence of the absence of highly developed extraterrestrial civilizations as such (therefore, this paradox is sometimes also called the Fermi-Hart paradox). So really, where are they?
And you can't get away from this question with statements like the fact that aliens are not inclined to travel (the hypothesis of potato beds) or surreptitiously watch us from the sidelines (the hypothesis of a zoo, where humanity is a rare and protected exhibit). Both of these hypotheses - and many others - suffer from one incorrigible flaw: they proceed from an unjustified premise that all extraterrestrial civilizations have some common quality: either all extraterrestrial civilizations are prone to pathological homebody, or all extraterrestrial civilizations have (and, moreover, it is strictly observed!) the same ethical principle of non-interference in alien affairs. But if there are thousands of civilizations in the visible space, their uniformity is practically impossible according to the theory of probability! Finally,mankind arranges nature reserves on Earth to protect rare game, but this does not always interfere with poaching.
Since 1961, searches for radio signals from extraterrestrial civilizations have repeatedly stopped, then resumed again. The results were invariably negative - there was no evidence of the existence of extraterrestrial intelligence. The history of such observations can be used to delineate boundaries in deep space beyond which the existence of technologically advanced civilizations is still probable. Today we know for certain, for example, that within a radius of 1000 light years from Earth in space there is not a single civilization that would generate signals in any of the ways known to us.
SETI scientists categorize civilizations by their ability to generate energy. Type I civilizations generate energy in amounts roughly equal to the amount of energy received by their planet from their star, and type II civilizations generate energy in the order of the energy emitted by their star. (According to this classification, mankind belongs to the "type 0.7" - on the Earth 70% of the amount of energy required to be called a type I civilization is produced.) Today it is safe to say that there are no type I civilizations within a radius of ten thousand light years from Earth, and civilizations of type II - not only within our Galaxy, but also in adjacent galaxies, which make up a single galactic cluster with it. Presumably, these limits will continue to expand.
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The economic aspect of the Fermi paradox by Josek
Scientist William Hosek in a specialized journal of the British Interplanetary Society expressed his opinion on the Fermi paradox. What is his scientifically based conclusion? "Humanity has not been visited and will not be visited by representatives of extraterrestrial civilizations, just as we will not visit them." Why is he so convinced of this?
Josek analyzes the Fermi paradox purely from an economic point of view. He believes - and in this he is probably right - that on any inhabited planet, the available raw materials will sooner or later be depleted. People, however, are not inclined to plan for the long term.
That is, they do not really think about the future beyond the segment of their own life - they do not think on the scale of centuries. Whether it's the public or private sector, national or international companies, no one invests in the ages to come, as they expect to get some kind of return “in life”: shareholder bonuses, winning the next election, and so on. If humanity sends a spaceship in search of raw materials, those who remain on Earth will never know if the expedition is successful or the crew will return empty-handed. What institution would want to invest billions of dollars in a project that does not guarantee any benefits? The human age is short and we want to see results.
In addition, the construction of a giant starship, designed for travel longer than a human life, would require not only astronomical amounts, but also a huge amount of valuable raw materials - the very raw materials, the reserves of which, in fact, are running out on the planet. It makes sense that such materials should not be risked for an incredibly expensive space project that will not bear fruit in the next hundreds of years - if it does.
Hosek attributes this “earthly” logic to civilizations outside the solar system as well. The result of his analysis is quite sobering. First, in order to get support from some alien civilization, we first need to get to know the "foreigners" and at least maintain regular radio contact with them. Secondly, an alien civilization must be more advanced than ours. Thirdly, it must be able to receive our messages, translate them and, finally, understand. Fourth, they must be prepared to provide us with the raw materials we need. Fifth, share your technology with us. Sixth, we must be able to use their equipment and instructions, and finally, the aliens, of course, must understand that their own raw materials will eventually run out. So it's hard to believethat some alien civilization decides to provide raw materials to another.
Sounds pretty convincing - from an economic point of view. Dr. William R. Hosek, author of this research paper, emphasizes that his findings are purely economic assumptions. Judging by which one can forget about the prospect of interplanetary communication, since we humans strive to obtain short-term results and simply do not have enough resources to build giant starships.
Erich Von Daniken "Twilight of the Gods".