The Fermi Paradox - Is there Alien life in the universe?

What is meant by the Fermi Paradox

and

How does Fermi Paradox explain the possibility of "alien life" in our universe?

Image credits- Pawel86- Pixabay

Let me just preface this entire post by adding a disclaimer: This post does NOT have any connections with the recent events relating to those ghostly flickering monoliths or the unknown radio signal we received from Proxima Centauri!

Whatever the answer may be, there's always this ONE universal question every relevant astrophysicist or cosmologist might get- 'Are we alone in the universe?' or 'Are there other intelligent life-forms in the universe?' or 'Are aliens responsible for the pyramids..!?' (which is probably my favourite of them all !!). But do these questions actually mean something real? Well, it turns out that there is a possibility of alien life out there after all, according to the Fermi Paradox. 

What is the Fermi Paradox?

 The Fermi Paradox was brought up by an Italian physicist, Enrico Fermi, who posed the question of the existence of extraterrestrial life in our universe. He didn't just imply the conclusion of alien life, rather he put forward this idea by precise calculations and probabilities. But did he impose this possibility?

We know that our universe is about 14 billion years old and there are more than 100 billion galaxies in the observable universe. Now, within each of these galaxies, there might be another 1000 billion or more stars, where each star possibly hosts a star system (like our Solar System). 

And within each of these star systems, there might be planets that are habitable, like our Earth for one. So, summing up, if we take the observable universe as a whole, there might be more than trillions of habitable planets, which can develop intelligent life forms. 

Space colonization- Image credits- ScienceHook

All of these facts built up to one crucial point- there should be more, if not, at least one intelligent life out there, longing to explore the vast universe, just like us humans. And even if there are alien civilizations out there in the universe, they should've reached out to us by now, since the earth was born after about 11 billion years after the Big Bang, which means other habitable planets could've evolved way before our earth!! 

Even in our Milky Way galaxy, there's a strong possibility of about 1 million planets that could support intelligent life, which could've attained a "super-civilization" phase, including colonization of an entire galaxy!                                                                                                                                           

But where are all the aliens? 

If all the above-said facts were correct, which they are, why haven't we found any alien life all this time? 

This question is what we call the Fermi Paradox.       

But till now, we haven't found any real answers to this paradox, or to be more clear, we still don't know if we're all alone in the universe. 

What might be the solutions?

Probably it's because these habitable planets couldn't develop organisms somehow, due to climate change or an asteroid attack, just like on our earth. And maybe our earth was just lucky enough to withstand all those natural disasters! Another reason may be that our universe is constantly expanding and that as time goes on, it'd be harder and longer for aliens to reach out to us and vice-versa.

 Or maybe it's just the fact that aliens might've passed by our planet and they didn't find any intelligent life here. Or we just didn't appeal as intelligent beings to them!!

 Well, if that's the case, then it's pretty depressing, after all we've done on earth ;)           

To know more about the Fermi paradox, watch video            

Also, read a paradox relating multiverse theories and quantum mechanics -  Schrodinger's cat paradox