“Where are they?” – Asked in 1950 an Italian physicist Enrico Fermi, talking with colleagues. Although the question was out of context, the interlocutors immediately realized that the scientist was referring to aliens. Fermi’s doubts were justified: the Milky Way is 13.2 billion years old, there are about 200 billion star systems, about 10% of these systems have planets similar to Earth, which means that people, in theory, have long had to find extraterrestrial intelligence or at least signs that it exists (or existed).
People are very lucky
Although there are potentially billions of planets similar to Earth, intelligent life (and life in principle) is a very fragile thing, according to some scientists. For example, it took a single-celled bacteria 1.7 billion years to evolve to a complex one. Any cosmic cataclysm near the solar system could destroy the simplest terrestrial organisms. Moreover, the aging stars shine brighter and because of it the planet’s climate becomes unsuitable for carbon organisms. But in the Earth there is a unique situation: even though the sun warms it all stronger, geological and biological processes constantly cool it, and therefore the temperature is always more or less normal.
People are looking for wrong things in wrong place
Our ideas about aliens are based on how the technologies invented by man work. But who said that on other planets and under other circumstances there are the same conditions as on Earth? A biologist Simon Conway Morris, insists that if the alien living organisms exist and they are like us, it does not mean that they leave similar traces.
Search for signs of intelligent life beyond Earth are limited mainly by radio waves. The idea is that they should easyly point out where the technologically advanced planets exist. But in response we hear only silence, or perhaps receive the necessary signals, but we can not interpret them correctly. More signals may be just lost in the cosmic noise or be fundamentally incomprehensible to us. So maybe it’s time to shift the focus – for example, to search for signs of other technologies, not hoping that the aliens necessarily broadcast radiowaves into space.
It is more profitable to intelligent life to be quiet
Aliens could be found if they didn’t hide from us, some researchers say. Canadian physicist Adrian Kent suggests that at the level of the cosmos the evolution may favor those who don’t cast their shadows and explores the universe only observing it.
If this scenario is realistic, then constraining the colonization of space is the evolutionary safest strategy. Americans Walter Simmons and Sandeep Pakvasa even figured out how alien civilization could exchange encrypted messages. For this, a message is divided in two, and both parts are sent in opposite directions, then they reach up to mirrors and get united at the point of destination. Even if someone besides the recipient could decrypt the message, no one could figure out from where it came. Kent also notes that people need to think about the consequences of recent decades: all this time we have been sending signals in all directions “Find us!” And even sentbeyond the solar system two “Voyageurs” Such a reckless behavior may not be good for humanity: if we assume that extraterrestrial intelligence exists, but do not know what it is, then we run a significant risk.
Humans and aliens haven’t found each other
Fermi paradox may be due to the fact that we are too impatient. According to Bill Nye, we just need to wait: we are trying to find extraterrestrial intelligence just 50-70 years and it’s a miserable period for the universe which is about 13.8 billion years old. The Fermi paradox should not convince us that the aliens do not exist. On the contrary, it should teach us that it is necessary to monitor and study the universe more, taking more affords in space exploration.