Scientists Explain: If Aliens Are Out There, Why Haven’t We Heard From Them Yet?

There is a very high likelihood that there are aliens out there, but at the same time, we currently do not have a single piece of evidence, aside from the sheer size of our galaxy and the universe, for us to be alone. This is a phenomenon called the Fermi Paradox, named after Enrico Fermi’s question: “Where is everybody?” .

Enrico Fermi was an Italian and a naturalized American physicist, famous for being the first scientist to create the first artificial nuclear reactor. However, he is more well-known for his question pertaining to the presence of extraterrestrial life and why we have not come into contact with any of them.

The Great Silence: Scale and Probability

The Fermi Paradox highlights the contradiction between the probability that there is an alien life form somewhere out there, due to the sheer scale of the Universe, and the lack of any detectable signals, visits, or signs.

Even if only a tiny fraction of all livable planets in the Galaxy host an intelligent civilization, we should have heard something by now, if they are at least closer to the technological advancement of our species. This begs the question: If aliens are out there, why haven’t we heard from them yet?

Read more: Wikipedia

The Great Filter: Rare or Deadly Steps

Why haven’t we found aliens? A physicist shares the most popular theories. | Brian Cox

One of the scientific theories that could answer the Fermi Paradox is the Great Filter. It states that life undergoes very complicated steps before reaching the levels our civilization has achieved. This includes the ability to evolve to reach an intelligence that could achieve longevity. One must also be capable of creating technology to bypass their natural limits.

The Great Filter suggests that the other alien civilization did not pass the early stages of evolution to survive, or to reach the intelligence that will allow them to contact us or send signals across the cosmos. In other words, at some point in their development, they faced a hurdle, a filter, or a barrier that prevented their civilization from improving or existing.

Hidden or Silent Civilizations

Another possible answer to the Fermi Paradox is that Alien civilizations avoided contact to prevent being annihilated by other extraterrestrial life forms, which might be more aggressive or more powerful, known as the Dark Forest hypothesis.

An additional theory includes the aestivation hypothesis, where a civilization maximizes its computational capabilities and waits until the far future to be more active. If any of these theories are right, then it means we are not alone, but the reason we do not have any evidence of them existing out there is because they do not want us to know they exist for the mentioned possible reason.

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Maybe We’re Not Listening Right

Another logical theory is that they are already speaking or sending signals to Earth, but we are operating in different wavelengths or technology, and we can’t listen to them correctly.

We are using radio signals, while they might try something like a technosignature that is unknown to mankind. It could be a burst of light or radiation, or something bigger at a scale we could not comprehend.

It could also be because their signals have not reached Earth yet, due to the sheer size of the universe. Earth’s radio signal itself only reaches about 200 light-years away, but they might exist in a few thousand light-years away or more.

So, it could mean that we need more time, either to analyze and receive their message if they are truly sending signals already, or to be able to develop better tools and technology to send our signals farther.

The REAL reason why we haven't heard from aliens

Author's Final Thoughts

There are more theories out there that could explain why we have not met any aliens yet that we have not discussed in this thought experiment, including the Post-Biological Hypothesis, the Simulation Hypothesis, the Zoo Hypothesis, the Transcension theory, and the First-In Last-Out theory.

The silence and lack of evidence we are experiencing is not proof that no other civilizations out there exist. It might just reflect the complexity of life, the danger other life forms pose, and the distance or differences we have.

We know this article ended up not answering the question in a definitive way, but there is a reason it is called a paradox, and until we solve it, the existence of aliens will remain a mystery.

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