The Fermi Paradox. Why Are We Alone In The Universe?

Cosmology Science Singularity
The Fermi Paradox
© / geopaul

Where Are They?

Nobel prize-winning Italian physicist Enrico Fermi asked the question "Where are they?" regarding the question of life existing elsewhere in the universe. If one assumes the mediocrity principle – that the development of life on earth is typical in comparison to the rest of the universe – we should see evidence of other life. The Fermi paradox is the contradiction between estimates of the number of extraterrestrial civilizations and a corresponding lack of evidence of these civilizations – both physical and radio (the Great Silence).

It's obvious that civilizations can exist – we are one. Why not others?


  • The universe is extremely old. Its current age is estimated at approximately 13.73 billion years
  • The number of stars in the visible universe is extremely large – approximately 5 x 1022.
  • Some of these stars will have habitable planets which develop intelligent life that can produce radio signals.
  • Interstellar travel is possible, and some civilizations desire to colonize stars.

More intelligent estimates of the Drake Equation have been possible with recent advances in astronomy and astrobiology. One estimate in the July 2000 edition of Scientific American suggests the number of civilizations that have existed in our galaxy in the past is 12 billion, with 1,000 of them still transmitting radio evidence of their existence.

Despite those assumptions, limited radio searches of the skies for nearly 50 years have found no evidence of extraterrestrial life. And, it would take only one civilization that desires so between 5 and 50 million years to colonize the entire galaxy – a blink of an eye compared to the age of the universe. So where are they?

Possible Solutions

Clearly there must be something wrong with assumptions that have been made. Some possible resolutions to the Fermi Paradox are:

  • A Great Filter drastically limits the number of civilizations in the universe. Life faces existential risks which are difficult to overcome. For example, the development of the ability to communicate by radio occurs at roughly the same time as the development of nuclear weapons. Professor Nick Bostrom claims that the lack of evidence of extraterrestrial life is a positive sign for the outcome of our own existence.

  • One or more of our assumptions is wrong. Perhaps we're not searching in the right way. Before the invention of radio, for example, the only way to search for life would have been optically. Perhaps neutrinos or some other communication method is used instead.

  • Transcendence – Life passing through a singularity stage may discover a way to exit the universe, or find more meaningful ways of existing. Maybe we are boring and they have no interest in making contact or communicating with us.

  • Perhaps we are living in a simulation.

  • The Zoo hypothesis – we are being isolated intentionally.

  • Perhaps abiogenesis occurs less frequently than current assumptions and we really are alone.

What do you think?


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13 thoughts on “The Fermi Paradox. Why Are We Alone In The Universe?

  1. I liked your discussion of the Fermi Paradox, Don. But I feel there is one other possibility that you avoid mentioning, : that current efforts at contact and communication are being filtered from within our own society.
    Since time immemorial, the common man and woman have been at the mercy of our Elite leaders, whether Priest-kings of Sumer who were the sole creatures allowed to ascend the ziggurat and converse with the Gods, or ancient astronomers who sighted star-paths over the long barrows of England and claimed they were in contact with the deceased spirits of our ancestors who lived on the Moon.
    Currently, we appear to be in a time of tremendous off-world (or trans-dimensional) visitation, if the vast number of sightings by ordinary, professional and military witnesses is any indication. That our own governments have been lying to us about these visitations is no longer debatable, since a blizzard of military and government documents are available to prove that very point.
    We are also being fed by our media a series of false impressions of the reality of these visitations. When a disc-shaped object appeared over Concourse C at O’Hare Airport in November of 2007 and was sighted by over twenty people (including pilots of landing airliners), none of the local media outlets chose to run the story. Only after it spread like wildfire through Internet sources, did an FAA spokesman deign to comment, and only then, to make a joke about how far “they” must have come, just to lose their luggage.
    When a giant triangle overflew most of the state of Arizona in March of 1997, the US Air Force chose to drop flares over Phoenix in an effort to obfuscate the earlier event. Not to be outdone, Republican Governor Fife Symington had an aid dress up in an alien costume at a press conference to ridicule those claiming to have witnessed the earlier event. Only ten years later did Symington have the courage to come forward and admit that he had himself witnessed the triangle shape, although why he needed to embarrass the other witnesses with a costumed aide remains something a mystery.
    From such officially ridicule and to popular films like “Men In Black” and “Mars Attacks,” the reality behind the visitations is made into the stuff of B-grade movie plots, if it’s bothered to be covered at all. There is limited intelligent perspective, of course: “Contact,” Carl Sagan’s farewell reversal of his long stand against intelligent discussion of the extraterrestrial question, accepts as a given not just that there are intelligent species out there ready to contact us, but that our own government would prefer to keep that bit information as quiet and undiscussed as possible.
    Is there intelligent life in the Universe, besides Douglas Adams’ dolphins and lab mice, that is? Undoubtedly.
    Would Washington or Whitehall share the minutes of any meeting between off-worlders and us lowly peons? Never.
    The longer we’re kept in the dark about what’s really been going on between our own Priest-kings and “them,” the longer we’re kept at the base of the pyramids, hauling stones and greasing the sledges.

  2. The Drake Equation is meaningless. We don’t know the value of *any* of the variables. Any at all. And while recent discoveries give us some possible bounds for those variables, those bounds are still so broad as to be virtually meaningless. There may be a billion civilizations out there–and there may be none. The Drake Equation is itself pseudoscientific. It says whatever we want it to say, not what *is*.
    The problem is not that our assumptions are wrong, although they most likely are. It’s that we don’t even begin to know what assumptions should be made. We are completely ignorant.
    It is a waste of time to even be thinking about how to contact other intelligent life. We simply have no idea how. They (if the term could even be applied) could be living right next door to us, relatively speaking, and the chances are good that we’d have no idea. I don’t think people have an adequate grasp of how “other” life could be. It might not even look alive to us. We might not look “alive” to them. The question itself is foolish. The universe is. We are part of the universe. “Other” life will be, too. That’s all we know. Perhaps if we’re lucky (very lucky) we’ll find it. But we can only do that by learning about the universe.
    Looking for other “beings” who “communicate” is assuming far too much about what our “neighbors” might look like. Pretty damned foolish, if you ask me.

  3. It could be that the signal is well on it’s way to Earth; it just has to travel another 59 light years before it gets here. The Universe is a BIG place.
    On the other hand; keep an eye out for marker probes that have been placed in our solar system; perhaps in retrograde orbits. Maybe out near Pluto. But we haven’t even gone to Mars yet. We are young nubiles.

  4. We are barely looking. The Allen Array only has some 40 some dishes and gets NO govt. funding. Meanwhile; trillions of dollars are poured down the toilet hole of unnecessary wars. Can you imagine how powerful the Allen Array would be with a Trillion dollars of govt funding?

  5. Perhaps our radio signals haven’t reached them either. How do we know our radio signals can travel far enough too reach other civilizations, especially since we haven’t been making them for a long enough time for them to have traveled that far yet. If the other civilizations near us have only progressed as far as we have then their signals would not have reached us yet either.

  6. …or those signals have already come and gone millions/billions of years ago? Our radio time slice in the universe is miniscule (radio age 200yrs/15 billion = 0.00000133%) – even if humans or other civilizations last 1 million years and produce radio signals that entire time (perhaps both are unlikely), that still leaves only a 1:15,000 chance of overlapping signals from overlapping civilizations. This also means we need to listen for another 999,800 years for this ratio to be disproved.
    Now if one presumes the radio age and the atomic age results in civilization destruction (also unlikely IMHO), then that chance of civilization overlap reduces to about 1:75,000,000.

  7. I think even if intelligent beings exist on some other planet what difference would it make to humankind. Looking at the history of the humankind it is clear that we are the most unfriendly creatures even to our own species. Look at wars, and killings, and humans are constantly in a race with each other. I know I am taking science philosophically here which is not quite sensible… But why, why grope so much for finding life on other planets. I bet if humans found life (or a possibility of life) on other planets they will destroy that planet the same way they are destroying this planet Earth.
    Science, sometimes, seems to me all absurd exercise.

  8. it is hard to say why we are alone as long as we do not have a definition of life outside organical chemistry.
    some time ago I’ve read “what is life” by Schrödinger. it was the book that made me think of so many things at once and I’ve made so many connections. this post is the result of all those thoughts:
    and i still couldn’t understand why we consider bugs alive but computers objects when the computers can process so much information! our brain is the organ that makes us identities or dead bodies and not our dna in the end

  9. Well put, ern. Seems to me so much of scientific effort gets hopelessly lost when the research begins to take on a sort of “let’s- play-what-if” mentality. Now, I understand that exploration has to begin with an idea, a hypothesis. That’s given. However, when one has spent half a lifetime going down the same hallway and never finding a door, one might begin to think that another hallway would be more productive. I say this not to ‘dis’ or exclude any random searchings; rather to say that, in my opinion, one would perhaps be more successful at finding something, anything, of value if they would at least occasionally measure the ‘return on investment’ (what has effort produced so far)and consider changing-at least by a few degrees-the focus of their purpose. Larry (

  10. But our brain would not exist if not for our DNA. The computer is a product of us and our brain and ultimately the DNA that created our brains.

  11. Why not send 10 500-megaton hydrogen bombs into space 90 degrees from the rotational axis of the solar system. Assemble a group of astronomers to determine the best location for maximum effect. Set the bombs off in a sequence that could not be mistaken for natural phenomena? Yes, it would still take light time for it to reach any advanced system but it seems to me that it would be a strong enough signal to be observed from long distances. Why not and how should we expect a reply? Just a thought.

  12. FIRST, OUR radio signals are irrelevant because we observe ZERO signals from anywhere.
    2nd, our galaxy, alone, is enough of a test case for the Drake. Forget the rest of the universe..if there is no life in the one galaxy we know there is life then we are the only ones.
    The Drake is a biased wish proposed by atheists who somehow believe that life springing up out of rocks is common when all the probabilities show the odds are effectively zero that amino acids could pair up randomly to create DNA–which BTW hold the exact spacial location of the 4 chamber Heart, its electrical frequency, pressure etc. To somehow be so naive as think consciousness could randomly build itself, even once, is lunacy and the sooner people start realizing that these atheists are the OJ Simpson jury the better off they are gonna be.
    The fine tuning of the universe and Earth for life is a scientific fact–but the jury is so afraid of the obvious conclusion because it dooms them. When the answer points to your own destruction–how in the world can you ever accept that answer? These guys have been in the first stage of grief–denial–for 40 years. Dont follow them. There is no one else in this universe

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