The Fermi Paradox


Where is everybody?

In their essence there is one element that binds many or even most theologies together: the notion that mankind is somehow special and part of a divine plan. In that sense none of these theologies predict the existence of (or even allow the possibility for) non-human intelligence.

The Atheistic position is entirely the opposite. Following the predictions of science, atheism considers it most likely that mankind came about through spontaneous processes that are not only plausible, but should be ubiquitous. They predict that life should be able to arise independently from our planet and allow for non-human intelligence to exist outside of the ‘Divine Plan’.

Hence we have two diametrical opposite ‘Theories’ with predictions that should yield observable consequences. And yet, for now however, it seems atheism is losing because, although absence of evidence is not evidence of absence, but still… Where is everybody?

Image of the Drake equation.
Image of the Drake equation. Depending on the variables plugged into the formula the Universe should be teaming with life or contain almost none of it.

The ‘Fermi Paradox’ is the popular name for a problem in cosmology. It is a misnomer as the problem was neither raised first by Enrico Fermi, nor primarily argued by him, nor does it contain an actual paradox. In its simplest form the problem states that, given what science has found out about our own ontology and its speed-of-development, taking into account that the Universe is already 13 billion years old, one would expect that by now other intelligences would have developed in the Universe and gotten to the level of technological advancement that we would be able to detect. Unfortunately, despite some investment in the SETI project, this has not been the case.

I’ll admit that at first this issue may seem rather dull, trivial or ‘nerdish’ to any reader. For some part it is also tarnished by UFO-conspiracy-believers, in such a way, that to merely mention ‘little green men’ is to instantly sacrifice your credibility. But the definite answer to this problem, if we ever get one, has the unmistakeable potential of being the single most important event in human-history to date. Future generations may one day look upon us, in history, and ignore the mark we made at 1492 (the linking-up of Europe and America) in favour of some, for us, future date on which we discovered proof of other Intelligent Life out there; If it is out there. There should be no doubt that if this would ever be the case, this would instantly demote all of us, dwellers of the past, to the ‘ignorant-, backward-, positively medieval‘ -section of history, much as we have done with our own ancestors. So I think the thought of this issue should not fill us with boredom. But rather make us profoundly envious of our descendants in this potential future.

It is at this point that I must quote the well-known Lawrence Krauss “The Universe is the way it is, whether we like it or not” for in particular in this discussion we tend to skew our estimates in favour of the, for ourselves, desired result and not vice-versa.

(I still support the ideas of Lawrence Krauss. This does not include support for the type of behaviour he is accused of having committed. Also, this post actually predates these events but remained unfinished for a longer period)

We must be careful not to let ‘how we want things to be’ or ‘how they would be more or less convenient’ dictate our analysis of ‘how it is’. This is also a good place to state that with respect to the Fermi Paradox literally entire books have been published. I can’t pretend to give more than an introduction to the subject in order to clarify my opinion on the matter and examine any consequences for atheism.

Creationism and the Fermi Paradox

There is no aspect of Creationism that is consistent with extra-terrestrial life and it appears this is actually something they worry about (discoveroids-solve-the-fermi-paradox). But perhaps it is better to say: creationism doesn’t predict extra-terrestrial life. All they have been saying, based on their little immutable books, is how unique and special mankind is and how everything below the heavens is made for man. You can bet your sweet sorry ass though that the moment alien-life is found they’ll be like “Yup, God did it!”. There’s actually already signs for this from the biblically-flexible Intelligent Design direction:

“here’s a real paradox for you. Allowing design as an option actually increases the chances of extraterrestrial intelligence, since there is then a way to overcome the extremely remote probabilities. If there is ETI out there, it’s thanks to ID.”

Judging by the creationists reactions to a soon-to-be peer-reviewed paper “Dissolving the Fermi Paradox” by Anders Sandberg, Eric Drexler and Toby Ord it is safe to say that most theists/creationists are still firmly on the ‘we are alone’ band-wagon (dissolving-the-fermi-paradox-guess-again). The fact that we haven’t found any alien life so far, can either be seen as an ‘observation’ in favour of Creationism or a temporary reprieve from what would be a devastating blow. Ignoring the latter for a moment, one would think that this argument ought to show up more often in creation-evolution-debates. In fact I would expect it all the time, as it seems to me that the Fermi Paradox has the potential of being one of the better arguments coming from the theists-side. After all when we follow the logical conclusions of the study of abiogenesis, evolution, geography and cosmology we have to come to the conclusion that ‘Life’, living matter, and to some extend Intelligent Life, should exist in more places than on Earth alone. In Science we maintain that theory must align with observations and, at the moment, it seems that observations agree more with Divine-plan-Earthly-creationism instead.

We should be humbled by this fact and perhaps alarmed by it, but we should also not throw out the baby with the bathwater: all the underlying sciences have a lot of supporting evidence that also disprove Creationism. That Creationism has a single observable fact that, at least for now, seems to not-disagree with it is hardly cause for celebrations. We should take it seriously none-the-less.

I did manage to find some creationist websites that addressed the Fermi Paradox. Neither their viewpoints nor their arguments proved much of a surprise:

“Assuming a naturalistic origin of the Universe, and assuming that random chemical processes were the cause of the origin and rise of life, the conclusion seemed inevitable: there MUST be multiple BILLIONS of technologically advanced civilizations in the Milky Way galaxy alone based upon even the most restrictive of scenarios. But if this were so, then the Earth ought to be positively DRENCHED in intelligently created radio signals from alien civilizations. Why then the deafening SILENCE screaming at the astronomers from the cosmos?”

“The secularists have a serious problem here…a very, very, very serious problem.”

We will see, in fact, that ‘Earth-drenched-in-radio-signals’ is somewhat hyperbolic nor is anyone in the scientific community actually very, very worried.

The Drake Equation

As one may imagine the Fermi Paradox is intimately related to the Drake Equation, which is a formula proposed by Frank Drake in 1961 that is intended to make an educated guess as to how many intelligent civilisations an average galaxy may hold. However, depending on the size of the assumed variables, different results ranging from less than 1 to several 10’s of thousands of civilisations-per-galaxy have been defended. We should take this as an indication that our best estimate for what we expect to find out there is not very precise. Since we have no idea how big the hole is, this makes it all the more difficult to find the right solution to plug the Fermi Paradox.

Looking for solutions


To help guide the vast landscape of solutions to the Fermi Paradox I’ve identified 4 factors that help classify these solutions. This is my own invention and I may even have disregarded aspects that others considered. Never the less it is a tool I introduce just to help you think about this matter in a slightly more systemic way.

  • Uniqueness/Rareness/Commonness:
    Either or all of these aspects could be unique, rare or common:
    1. Earth
    2. Life
    3. Complex life
    4. Intelligent Life
  • Simultaneity:
    • Phenomena could be occurring during the slice of time we occupy
    • Precede us
    • Succeed our existence.
  • Duration:
    • Phenomena could have open endings
    • Relatively long duration windows
    • Short abruptly endings histories
  • Separation:
    • Phenomena could be spaced beyond a absolute event horizon (the space between two places expands more quickly than light can traverse)
    • They could be spaced beyond a pragmatic event horizon (Light cannot cross the space in the duration that both phenomena of life co-exist)
    • They could be close enough that at least one of them can receive a signal
    • They could be close enough to be able to exchange signals.

On a purely mathematical-quantitative level these factors can yield 2916 different combinations. Fortunately, qualitatively speaking, it is clear that not all of these combinations are possible; that some yield results that are not-distinguishable from each other and that some are clearly more likely than others. For instance all combinations in which Earth or Life is unique have the same bottom-line result. Combinations where Earth is rare but Intelligence is common are not possible. Civilisations with an open ending seem very improbable by themselves or at least do not rime with Earths extinction events. Also the combination of rarity and small spatial separation is highly unlikely; as is the combination of rarity with short duration and simultaneity. Finally there are combinations that do not match observations. Such as the combination were Intelligent Life is common, with long durations, simultaneity and short distances of separation. This would mean we’d already be in contact with alien civilisations, which is not the case, or is it?


One way of solving any problem is by denying that any such problem even exists. It is exactly this what UFO-conspiracists do: they claim aliens have visited us and the reason we are not all acutely aware of this is a mixture of ‘government’, ‘implants’ and ‘erased minds’. Mind you, I used to be one of these conspiracists, when I was 9 and I had read an ‘adult’ book full of eyewitness statements. There was only one problem though: the book implicitly predicted that aliens were both simultaneously rare as well as abundant. Apparently the government had no problem hiding the ‘sightings’, but at the same time very few ‘sightings’ had much in common. Suggesting that either we were being visited by a wide variety of alien-life or perhaps by a handful of species from multiple eras.

This internal contradiction begged for a simple explanation, which is this: in reality aliens have not visited us, ever! Instead, largely based on and coinciding with science-fiction content, UFO-spotters are a cargo-cult of people whom, like with any religion, have a deep founded desire to exercise greater control over the world. Believing in UFO’s creates a world where vast, all-powerful technology is at our fingertips and, like with prayer, where ‘exposing’ the conspiracy is a way to unlock this power and gain greater control over one’s destiny. It does not address the Fermi Paradox in any serious manner.

Rare Earth Hypothesis

The rare Earth hypothesis is a collection of ideas that solve the Fermi Paradox by focusing on the astronomically small odds that were involved with our ontology and the number of such incredibly unlikely conditions that needed to follow one after another in order for us to be here. To list some of the conditions that were absolutely necessary precursors to our existence:

  • the Milky Way’s low incidence of galactically collisions
  • the location of our Sun in the galaxy(10% habitable zone)
  • the size of our Sun
  • the distance of Earth to the Sun
  • the size of Earth
  • the presence of a large moon at close distance
  • a big planet like Jupiter to suck-up the meteors
  • the ellipse with which we ‘circle’ the Sun
  • Earths angular momentum(not-tidally locked with Sun)
  • the angle of rotation of Earth compared to that ellipsoid(to make seasons)
  • liquid water and water cycle(precipitation)
  • an atmosphere
  • plate tectonics
  • volcanic activity
  • the combination of CO2 breathers and O2 breathers
  • the presence of metal on Earth
  • the Chicxulub impactor
  • periodic ice ages (and their warming)

While I don’t think any of these thinkers positively states that we must be alone in the Universe, they ask us to consider that this may very well be the case. This often is linked with an environmental message wherein it is emphasized, given how rare our planet is, how rare we are, not to jeopardise this.

With respect to the Fermi Paradox this hypothesis argues in favour of using small variables when applying the Drake equations. While I find this collection very noteworthy and their arguments very compelling I also must submit that these people are basing themselves on the same limited dataset we have all been using. Mankind’s semi-blindness in space favours ‘not finding many things’, this does not make them rare in an absolute sense. Our observations must therefore necessarily contain bias towards rare-Earthism. Which is not the same as saying they are wrong.

Besides on the factor of Earths rarity it must be clear ‘rare-Earthers’ are implicitly also weighing in on the simultaneity factor and the separation factor. We would be very surprised if rare phenomena occurred near each other in space and time. It may therefore not make all that much difference if the rare-Earthers are off by several orders of magnitude. With more stars in the Universe than grains of sand on our beaches, if even a million of those have a planet with a civilisation on it in their orbit, this is much too ‘rare’ to estimate the probability for ‘first-contact’ at any meaningful level.

In recent years the rare-Earth ideas have been forced to make a shift as more and more evidence has emerged that pushes abiogenesis, the making of living matter from dead-matter, closer to the solidification of Earth. This entails that the abiogenesis itself has a much higher probability than long assumed and in turn contributes less to an explanation for the Fermi Paradox. Simultaneously, where we used to find none, finding planets in the ‘Goldilocks zone’ around a star, where water can be liquid, has become a common thing. Partly to salvage the hypothesis there has been a shift to raise the probabilities of factors that support basic life while reducing the factors that support Complex- and Intelligent Life. This may feel as a cop-out, but it actually has a lot going for it. Primitive life arose on Earth in a cosmological eye blink but it took 99.9% of Earths-lifetime to create the conditions for Intelligent Life. While primitive life, case in point are stromatolites, can literally survive be billions of years, 99% of all more complex species has been eradicated. From this we can predict we’ll find evidence for non-terrestrial primitive life somewhere in the next two decades, while this does not also suggest that alien-complex-life exists or will ever be discovered.

Common Earth Hypothesis

Where rare-Earth departs from the idea that the conditions on the planet Earth are a-typical other collections of ideas on this topic depart from the opposite notion, that Earth can be taken as a typical planet with many siblings. To run the risk of making an appeal to authority, Carl Sagan, was an advocate of this position. Where certain rare-Earthers draw the line, saying that planets like ours that support complex life are rare, common-Earthers tend to blame invisible walls that prevent life, complex life or Intelligent Life; walls that have nothing to do with the probability of getting a planet like our own.

While I suspect that abiogenesis was not an incredibly big hurdle in our history the best proof of that would be to actually find evidence of single cellular life on other planets. There certainly are still aspects of it that are in a hypothetical state (proposals of how things could have happened rather than positive affirmations of how things did happen). But even after self-replication had commenced, several other pretty important steps were taken on our route towards Intelligent Life.

  1. Abiogenesis (the arise of self-replicating molecules)
  2. Endosymbiosis (where the first eukaryotic cell was formed from two single cell organisms)
  3. Multicellular life
  4. Sexual reproduction
  5. Colonial Expansion

These are what are called ‘Great Filters’ and they mostly focus on the rarity of phenomena surrounding Life. Only the last of the Great Filters, Colonial expansion, is different. Not only because it is the one factor we haven’t passed ourselves [yet] but also because it is more relevant for the duration/simultaneity factors: all life is limited both is resources it has available at the planet of origin and by the life-span of its neighbouring star. Civilisations that don’t make it off their initial planet are likely not to last long enough to cross the spatial separation with signals.

At the extreme end of the Great Filters-spectrum lays the Self-destruction Hypothesis. This collection of thoughts expands on our species self-inflicted problems with the idea that perhaps Intelligent Life tends to exterminate itself in predictable ways. When you look at life as a mathematical system it is plausible that it is stable in one state, but quickly unravels in another. The advanced state of technology that is required for us to make our presence known across a relevant section of the galaxy may lay beyond the point where such a society becomes self-destructive. That this may be the case is suggested by the fact that every necessary advancement we made to get to this point, posed increasingly impacting problems for the continuation of our survival. We now own the weapons that are capable of ending life on Earth (like a gun-owner who is the statistically most likely victim of his own weapon). We also destabilised (and keep destabilizing) our climate to the point of perhaps quickly rendering the planet unsuitable for life. Since humility is actually only as rational as hubris is, we must consider the possibility that we may not be very unique in this aspect.

Other common Earth hypotheses focus on the spatial element, the level of technology that would be required to cross it with signals, the amount of energy that would be involved with this and the level of incentives that would be required for an alien civilisation to do this. It has been speculated that in order to guarantee visibility across any kind of relevant distance a civilisation would at least require the knowhow to build and use Dyson-spheres. Judging by ourselves this is not something we, not even chief-optimist Elon Musk, are currently even speculating about.

Factors of uncertainty

Apart from the factors that we have already addressed several others have been suggested. These may or may not be actually contributing elements. Some of these factors have to do with us: perhaps we haven’t been listening for long enough, which is plausible, but it also means our data in not representative enough. Perhaps we have not been listening in the correct way or for the correct signal: it is certainly not impossible that we are so heavily biased in our expectations, of what a signal should look like, that we actually miss it. At the moment we are mostly looking for signs in the electromagnetic spectrum, but it is possible this technology represents only a small section in a civilisations’ technological evolution. Perhaps they are using better shielded types of technology now.
Other factors have to do with the supposed alien intelligence: would they even desire to communicate? Would they instead not prefer a low signal profile and literally hide among the stars? They might simply not be as curious as we are. Others say that aliens are maybe a lot like us, in that they are listening very hard but, like us, not sending a very powerful signal out.

The silence of the creationists

If you compare how often atheists are accused of ‘denying the God they know to exist’ or even ‘hating God’, while in reality we just find the concept of ‘God’ ridiculously simplistic, you would think a rare genuine argument like the Fermi Paradox would come up more often. Granted, once one goes looking for them it isn’t that hard to find discussions on the Fermi Paradox from the ‘other side’. Still there is a relative silence from the creationist side that, to me, is indicative of an avoidance of this topic by theists. The reason for this is two-fold I think:

  1. On the one hand there is a vocal minority of ‘young-Earth’ theists that deny anything existed before 6000 years ago. This is directly contradicted by the premises of the Fermi Paradox. They themselves, nor the people that don’t wish to alienate them (no pun intended), will therefore raise this argument.
  2. Then there are those theists who intuitively realise that the scope of their religion is positively colloquial compared to the vast expanses of space and time. Impressions of which are unavoidable when trying to scrutinise the Fermi Paradox. Even though their intuition couldn’t possibly approach the orders of magnitude of reality, even so they get struck with a religious kind of agoraphobia. With the Fermi Paradox finding itself way outside the comforts of their house of worship, like their real-world agoraphobic counterparts, they simply prefer to remain indoors.

Therefore the kind of theist that actually throws this argument in godless faces tends to be a more educated, perhaps a more worldly kind of theist. Less well-versed in the (all too constraining) lines of scripture, but no less convinced that he was intelligently designed to be special. And boy are they special! These are the people that don’t miss a beat between learning their ‘Gawd’ made a flat, rocky surface with a firmament; and between discovering that this deity also made the dozens of previously unknown planets around 100’s of billions of stars in each of the 100’s of billions of galaxies. In order to ‘keep their God’ they must now pretend it is self-evident that 99.999999999999999999…% of ‘creation’ was left out of each and every creation-myth the world has ever known. It is the religious equivalent of kids in kindergarten bragging ‘my father can lift a car’ immediately followed by ‘my father can lift the Sun!’. Neither off which is true obviously, but this does not imply that to believe them would require anything in the same order of stupidity. This explains why, while the young Earth creationist tend to focus on verses from Genesis and Deuteronomy, the Fermi-Paradox-wielding-theist takes his queue straight from the Abiogenesis-denying ID-mantra:

“The Universe did not have a naturalistic origin, it was created by a Creator. And it is simply IMPOSSIBLE for living organisms to arise on their own by chance chemical processes. As Michael Behe has pointed out, living organisms are comprised of IRREDUCIBLY COMPLEX systems at the sub-cellular level.”
“One thing is certain; those who do not recognize the Creator of all that is seen and unseen in our spectacular Universe will continue looking for life in all the wrong places. We know that God spoke the Universe into existence in six literal 24-hour days and rested on the 7th day declaring everything He had created to be “very good,” Gen. 1:21.”

“Because these men and women have swallowed the Theory of Evolution hook, line and sinker, they are certain that there must be a planet somewhere out there that can sustain life. They ignore the scientists that claim the odds against rocks transforming into men are statistically nil.”

The clever observer may see that there is a noticeable difference in focus between why these theists think we are alone in the Universe and why scientists think we haven’t heard from anyone. Creationists blame the Fermi Paradox on the fact that Abiogenesis and Evolution aren’t possible. Yet while the first is mentioned earlier as a hurdle for Intelligent Life it is not the greatest filter by far. The reason Evolution isn’t even mentioned at all is because it’s not a hurdle but rather a harsh if unavoidable accelerator to life. God himself, should he actually exist after all, wouldn’t deny he applied a gene-based-mechanism (where the fittest-elements for a situation got to reproduce more) to do his bidding. While they actually miss most of the underlying concerns of the Fermi Paradox it is kind of ironic that the theists above don’t see the implicit circular reasoning of their argument: ‘Creationism is true because otherwise we’d see alien civilisations all around. But we will never see any of such civilisations, because abiogenesis and evolution are impossible and creationism is true.’

Were is everybody?

So then, if not for abiogenesis or evolution, why aren’t we seeing any signs of anyone? The short answer is that the question assumes too much. It assumes there has been a small but relevant window of opportunity, during which we have applied a not-inadequate search-method with disappointing results. Yet these assumptions are entirely wrong and this is partially because of how optimistically Carl Sagan and others have been talking about our own signal we have been sending into space. The span of time we have been looking however was quite insignificant and the search-methodology non-systematic and severely limited by the laws of physics. The results are therefore exactly what they should have been expected to be.

Image of Neptune taken by Voyager II on its flyby in 1989.
Image of Neptune taken by Voyager II on its flyby in 1989.”

Anyone typing in ‘images from space’ into google-images will have a hard time believing this, but visually speaking mankind is almost blind in space. ‘But we have such pretty pictures from all these planets in our Solar System’ I hear you say. Well yes we do, but we didn’t take them from Earth and we only send probes to take those pictures after we already knew where to find these planets. Just compare the best possible picture of Pluto taken by the Hubble Space telescope (the best visual telescope we’ve ever made) with the images send to us by the New Horizon’s mission. It is clear that even objects way more conspicuous than anything mankind has ever made are hard to find.

Split image with a grainy shot of Pluto by Hubble on the left and a well-defined version from the New Horizon's mission on the right.
Split image with a grainy shot of Pluto by Hubble on the left and a well-defined version from the New Horizon’s mission on the right. It is clear that observing things from Earth is optically challenging. (from nasa)

Shortly after the demotion of Pluto, Nasa announced that calculations indicated there is almost certainly another undiscovered planet in our Solar System (see As it is likely on a rather eccentric orbit we are having trouble finding it. Not that this is unexpected. But just consider: if this planet exists it is expected to be 10 times Earths size, in our proverbial backyard, and we expect it will take 10 years to confirm its existence. Because even for optically finding an entire planet within our own Solar System, physics is quite unforgiving. So I’m not taking any risks when I say that the chance to find visual signs of life from outside our Solar System should therefore be considered non-existent. Perhaps you think me extremely naïve when I talk about visually detecting aliens, as if I don’t realise we are listening to space with radio telescopes instead of just looking at it. Don’t condemn me too hard for this. I was just covering my bases because, after all, we have been looking at the sky (with inferior lenses) for a whole lot longer than we’ve been listening to it.

We discovered our first pulsar (a rapidly rotating neutron star that emits regular pulses of radio waves) in 1967. Given the size and energy of this natural radio-transmitter this is the cosmologic equivalent of hearing a maxed-out sound-system from the inside of the car it was installed in. In other words, before 1967, we were kind of deaf as well as blind. So basically we have been listening for signs of alien life for only about 50 years. Now despite that the Universe began around 13 billion years ago a significant part of that time would have been spend on cooling down and composing elements heavier than nitrogen and helium. So if we graciously assume that no civilisations could have existed in the first half of the age of the Universe (See Hawkings ‘Life in the Universe’); Trying to find another civilisation in a 50-years-window is like making an appointment (with no-one in particular), ‘somewhere in the Solar System’, at a time ‘sometime between tomorrow and the day after’ and giving up after only 600 microseconds! Not to say that it was impossible that we’d have ‘met’ someone in this timeframe but it would definitely have required that the Universe was a crowded as Times Square on New-year’s eve. It also requires that the other party’s civilisation lasted 1000’s of times longer than ours has and has been sending out signals (preferably intentionally) since the earliest dinosaurs roamed the Earth.

There is definitely a tendency to see ourselves as ‘new-kids-on-the-block’, to assume that most Intelligent Life would have preceded us and that it’d be more advanced than we are as a consequence of their being around for a lot longer. In reality the earlier Universe had bigger stars that tended to burn out a lot faster, significantly shortening the window for complex life to arise. Speaking in probabilities the most likely point for alien civilisations to arise is well into our future. Red dwarfs with 0.1 solar masses could support habitable planets for trillions instead of millions of years. ( see ‘Universe today’). Much of the notion that we’d be able to detect alien civilisations at all, unconsciously extrapolates from the level of technology we see ourselves having in a couple of millennia from today. But if anything, while underestimating change on a personal level in our own lives, we tend to exponentially overestimate our progress as a species. For this we need only look at the achievements mankind is supposed to have made in popular Sci-Fi movies whose projected dates are now well passed us: ‘The Jetsons’, ‘Back to the Future’ and ‘Space 1999’.

The image of the more advanced and much older alien civilisation is also implied in Carl Sagan’s feel-good-moment where he underlined how far mankind’s radio-signals have already penetrated space. But radio-signals are still waves and thus subject to the inverse-square law: the intensity of the signal drops with the square of the distance. With a directional antenna we can still receive Voyager I, just outside our Solar System, 17 light hours away. It would require at least a signal 20 times stronger than our ‘loudest’ television broadcast in order for a civilisation like ours to receive radio-broadcasts from us on Alpha Centauri (the closest star-system) with the same strength. Only when directing an antenna straight at Earth would this signal be detectable. (see Brian Koberlein ) Improvements to our own receiver-sensitivity have allowed us to reduce (not enhance) the strength of our own emissions in the mean time. We are therefore even less detectable now, barely a century in, than we used to be.

To illustrate how hard it would be to radio-communicate with even our closest neighboring star system: Here is a clever idea for a communication-devise that is exclusively aimed at Alpha Centauri. The idea is to use a transmitter-relay that uses the Sun’s gravitational lensing to amplify the radio-signal in the direction of Alpha Centauri. The only caveat is that the transmitter would need to be placed outside our Solar System, around 76 light-hours from the Sun. (see: Centauri Dreams)

Now imagine that a signal would have to come from somewhere else in our galaxy, the centre of which is 50.000 light-years away (11.000 times the distance to Alpha Centauri). The chance that we’d be able to hear anything using radio-telescopes becomes literally astronomically small. Well then maybe, if radio is too ‘lossy’ and provided we’d be able to find out where aliens lived some other way, maybe we could use direction lasers to communicate with them instead? Well as a stand-in proof-of-concept let’s take a look at the moon-reflector-experiment: in which we shoot a range-finding-laser at the moon to determine its distance. This is basically what we’d be looking for in a laser-communication-devise: a narrowly aimed laser intended to maximally convey photons over longer distances. But even here results are disheartening. The 3 meter wide beam is already 6 Km wide when it reaches the moon. The return signal is 15 Km wide. Because only a fraction hits the mirror on the moon only 1 in 1017th photons is received on Earth. But even removing the mirror-reflection-factor and using a receiving-mirror-parabola the size of man’s biggest radio-telescope, 500m, we would only get 1/7 photons if someone fired a laser beam at us from only 2 times the moon-Earth distance. We are meanwhile casually neglecting the fact that the biggest actual telescope mirror man has so far made is 10 meter in diameter and making it was a significant technical achievement.

Radio-antenna have a roughly 1000 times larger divergence than laser but its receivers are a lot less cumbersome. Even using a hypothetical-futuristic directional-communication-devise with the signal-loss-rate of a laser but with ease of reception of a radio-telescope, a civilisation, if not exponentially more advanced than us, would not be omnidirectionally detectable, even if it lived only as far as the edge of our Solar System. By contrast, directed communication requires that both civilisations are already aware of each other and have established a relativity-proof protocol of communication. At the speeds bodies inside the Solar System move, making the connection would be the equivalent of getting two supersonic .50cal bullets to collide mid-air after being fired ‘simultaneously’ at perpendicular angles. In the 800.000 square-light-years of the Milky Way Galaxy there could be 100’s of civilisations exactly like ours and we’d have no idea they were there; and most if not all would go extinct without ever having known they were not alone.

I don’t think there are so many civilisations in our galaxy. I think the Rare-Earth-theory has some very good arguments why we should not expect to have a Universe teeming with complex life. While it does allow for the possibility of a Universe where only 1 instance of complex life arises it does not advocate this or make this very probably. In fact Steve Shives, a known youtube atheist, discussed the Rare Earth Theory on youtube recently in which he yielded to the arguments of the hypothesis. He discussed in it a practical application of the Rare-Earth-Equation, which, following the reasoning of the Drake-equation, tries to make an estimation of the number of planets in our galaxy with complex life. N = N* . ne . fg . fp . fpm . fi . fc . fl . fm . fj . fme(follow the wiki link for clarification).Using deliberately low estimates for each of the factors he arrives at 100’s of planets with complex life within our own galaxy. When he used even lower numbers he still arrived a minimum of 10. How many of those would reach our level of intelligence is not estimated. Extrapolating from a Hubble scanning of a part of the night-sky there are easily 100 billion galaxies in our Universe. There could actually be twice that considering the limitations we know Hubble has. If from the 10’s or 100’s of instances of complex life only 1 in 2 galaxies developed Intelligent Life this would still mean we have at least 50 billion intelligent civilisations in our Universe. Even taking Rare Earth arguments to an extreme this would still mean theists were wrong by 49999999999 civilisations or 99,999999998%. While it is highly improbable and hard to receive signals from even ‘nearby’ galaxies, proving the existence of other civilisations, it is clearly even more improbable that no such civilisations exist at all.

Yet for all this ‘Life’ in the Universe it is also clear we’d have very little change of seeing much or any of it. If only 1 in 2 galaxies contains Intelligent Life we’d only have a 1 in 4 chance that our next-door neighbour, the Andromeda Galaxy, also gave rise to such a civilisation. If Andromeda contained an advanced civilisation at some point after the Universe allowed for carbon-chemistry; A civilisation that was broadcasting sufficiently loud for us to receive and did so for as long as a million years uninterrupted, they still would have had only a 1 in 6000 chance of finding our current civilisation here on Earth listening some time in the period their signal passed the Sun. Assuming we could reply immediately, by the time they’d receive a reply message, they’d already be extinct for at least 4 million years. For perspective: 4 million years ago mankind was just a twinkle in the eye of an Australopithecus.

The furthest galaxy we are aware of is GN-Z11. This galaxy was 13.4 billion light years away from us at time the light we observe now departed. (With cosmological expansion, present distance is estimated to be around 32 billion light-years. The light-signal is single way though, ‘our’ light will never reach it since the intermediate space inflates faster than light can cross it). The distance to the edge of the Solar System, the furthest stabile radio-communication mankind has established so far, is only 0.0000000000144% of that distance. For comparison: there is at least 2 million times more uranium in normal soil. Our efforts to impact the reachable Universe have yet to surpass the level of a grain-of-sand falling into the Sun.


The question ‘Were is everybody?’ is basically an attempt to short-circuit the unknowns inside the Drake-equation ‘top-down’ by finding actual alien intelligence and working backwards from it. Having discussed the size of the Universe, the limits to our detection-range both in technology as in duration it should be clear that for most solutions to the Drake-equation this is not a viable strategy. Unless alien life is actually standing on our toes we’d be hard pressed to detect it. While it is not a bad or even a stupid question to ask, we simply haven’t earned the right to ask it. The absence of any such detection in this phase however, is absolutely not proof of absence. Despite the great number of unknowns still before us, we have steadily made progress in adjusting the likelihoods of certain factors in the Drake-equation. We are actually detecting habitable planets outside our Solar System and we have good hope that we’ll find evidence for life on Mars. The rover Curiosity found an ‘abundance of organic compounds on Mars’. One of which, methane, is the things that you, your dog, bacteria and a cow have in common. On Mars, by the way, its atmospheric concentrations are cyclical, which is intriguing

Our expectation of finding non-human intelligence, via a brute-force search, collides with some very restricting laws in physics regarding space-time, speed, wave-energy propagation as well as some limits to our own biology. This search-strategy is also markedly different from how we went about finding the Higgs-boson; which wasn’t found by randomly colliding large particles and seeing what -if anything- came out. Like with the Higgs, if at all possible, we will only find alien intelligence after we can predict to 90% certainty where it will be found and how we will be able to communicate with it. We will only do that by solving most of the Drake-equation ‘bottom-up’, by puzzling together the underlying answers. Even then it should take us a 1000 years or more just to get it confirmed.

..and theists?

So will theist be able to keep utilising the Fermi Paradox as a sign of ‘secular-failure’ and proof for a man-focussed divine plan? Actually not. While a signal from outer space would indeed (temporarily) destroy their theology (new ‘alien-included’ religions would arise with almost no interval) there is no rational reason to expect said signal. Instead it is important to notice that no theology takes a position on the ‘amount of planets in the habitable zone that are not tidally locked with their stars’. Nor do they predict (or care about) the impact of nearby moon-like satellites or any of the other factors that actually determine the outcome of the Drake-equation and thus answer the Fermi Paradox. Instead their stake within the Fermi Paradox stand or falls with the very first ‘bottom-up’ factor: abiogenesis. Once evidence for extra-terrestrial self-replication is found the myth of terrestrial-intelligent-design is falsified. Once life is shown to have spontaneously emerged outside of Earth, ‘divine-creation’ is not a better explanation for Life on Earth either. Nor is divine-creation a good explanation for life on Mars ‘an sich’. In the absence of Intelligent Life, such a design has no good Divine reason. It’s like putting a boat on the Moon, where in absence of water, it has no function or meaning.

The Universe is the way it is whether we like it or not and we may never be able to quell this cosmic loneliness. At some point in the future no galaxy will even be close enough to another galaxy to be able to see it. So net-loneliness in the Universe is only going to increase and the fate of any alien intelligence will be a lot like that of us humans. Trapped on this sinking vessel, on a prison without walls or escape. Drifting in the middle of nowhere, isolated from everywhere else; with no means of getting there or even alerting anyone else to our presence. Dying, much as we emerged, without a reason, without a plan, or meaning …or witnesses.

Uncommon Valour

Lest you wish to escape this dreadful fate
the nearing of that final date
In the hands of God no solace to find
The last thought inside man’s dying mind
‘Deus lo vult’.
God wills it, clearly commands it,
to have our kind
forever annulled.

Thus leaving creation empty and void,
apart for plasma and our loneliest droid.
Space now ridden and deprived of all meaning,
barren of the life of which once it was teeming

No matter how hard a fight as they try
to battle their outrageous fortune.
That day is also when all of man’s Gods must die.
Memes inflated beyond any proportion.

To be or not to be,
is not theirs to question.
They are just an idea,
a one man’s contention,
belonging to minds as waves to a sea.

Through love and fight
we’ve had a good ride.
But stories have zeniths.
due to thermodynamics.

Though we are now done,
we’re not the last one.
For while we’re alone,
other will come,
and assimilate every atom
from our bones.

Perhaps, one day, our hearts they’ll restore,
send a picture of it to Mars’ Curiosity.
Whom will reply them with a beautiful story,
of mankind’s love and wars and uncommon valour.

Live Long and Prosper


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