“Where is everyone?”. This simple yet deeply profound existential question was asked by the renowned Italian-American physicist Enrico Fermi one day at lunch with colleagues. He was referring of course to aliens. More specifically he was asking why humans have not yet discovered evidence of extraterrestrial life outside of Earth given the fact we’ve been observing and studying the universe and searching for signs of alien civilizations for so long, yet have we still have found no evidence of their existence.
Given the age of the universe at 13.8 billion years old, that is more than enough time for many life forms to develop independently on billions of planets and evolve into highly advanced technological civilizations with the capability for interstellar travel throughout the galaxy.
We should be able to see evidence of their existence. The universe is so old that it should be teeming with life, but again, to date, there is no evidence that life exists outside our planet or our solar system.
So where is everyone? That is a good question.
I think it could be easily explainable. Aliens exist but we just can’t see them because we’re not looking for the right kind of aliens.
We’re primarily searching for evidence of biological life forms, biosignatures from organic life in the atmospheres of exoplanets, and also radio signals. However, I think the reason why we haven’t found anything yet is because of timing, the physics of evolution on cosmic timescales, and our own technological advancement and limitations of our technology.
There are multiple methods science uses to detect life outside our planet. First.
Radio signals from technologically advanced civilizations would be very difficult if not impossible to detect because the ability to detect a radio signal is a matter of timing based on how long an alien civilization would be broadcasting radio signals.
Humans for example only developed and used radio communications for a brief period in our existence. Now we use digital instead of analog communications, meaning there is only a small bubble of radio signal that stretches out around our planet about 100 light years in distance. Unless we transmit more radio signals into space that bubble has a beginning and end.
Meaning that for an alien civilization to detect our radio signals they would have to be listening not just in our general direction, but they would also have to be within 100 light years of our planet, since 100 years is how long ago we started transmitting radio signals. Those signals (traveling at the speed of light) have only traveled 100 light years.
Another problem exists that probably makes it nearly impossible to detect radio signals from from other technologically advanced civilizations.
Radio signals deteriorate over time and distance. Radio signals get weaker over time and distance and therefore become considerably more difficult to detect the further they travel. This means the technology needed to detect those weaker signals would have to be more advanced and more sensitive, and that has a limit given the vast amount of time it takes for radio signals to travel between star systems.
The odds that any technologically advanced civilization (including us) would be listening at precisely the right time, in the right direction for the right duration of time and on the correct frequency are very low.
There are also limitations to how sensitive radio communication technologies can be. The sensitivity of a radio telescope for example is directly proportional to not only the size of the receiver but also the level of advancement of that technology.
Factor in time and distance and direction and timing and signal strength and you can see that actually detecting an alien radio signal becomes extremely difficult if not impossible.
The statistical probability of detecting a signal from another alien world in the vast reaches of the cosmos are so astronomically low that it is highly unlikely that any radio signals from any alien civilization will ever be detected.
This is where the term “The Great Silence” comes from. It’s pretty darn quiet out there. It doesn’t mean there are no aliens. It doesn’t mean we’re alone in the universe. In fact, it doesn’t really mean anything other than we likely missed the opportunity to detect any life forms that developed and evolved millions or even billions of years before humans.
If they exist and the laws of physics are the same throughout the universe, as our observations and data suggests, then we have to assume that alien civilizations also advance their technology at or near the same rate of advancement and in similar ways. There is a speed limit of evolution and of technological advancement.
Meaning that if alien civilizations evolved millions or billions of years ago in our galaxy, (depending on how far they are away from our planet) then the radio signals they emitted millions and billions of years ago have come and gone long ago and are no longer detectable by us.
BIOSIGNATURES OF ORGANIC COMPOUNDS, ALIEN LIFE AND TECHNOLOGICALLY ADVANCED CIVILIZATIONS
Biosignatures from organics or life forms on other planets could be detectable only if we have technology capable of detecting them. Which we do, but it’s limited in how sensitive the technology is and even then if we do detect evidence of organic compounds in the atmospheres of exoplanets, that doesn’t necessarily mean that it’s evidence of alien life.
It could simply be the result of another chemical process we have yet to be able to explain scientifically.
We’re also assuming that biological life is the primary or even the pinnacle of alien life.
In other words, we may be searching for the wrong evidence of alien life in Biosignatures. These biosignatures could be from other natural processes that are not necessarily indicative of aliens. Therefore if we do find these so-called biosignatures, it might not be aliens.
Also, even if we do detect biosignatures and we determine them indeed to be evidence of alien life, it doesn’t mean they are technologically advanced. They could simply be microbes. Odds are if we do detect those biosignatures it will be from planets with trillions of microbes. Yes, that would be aliens by definition, but not the kind we’re really looking for.
Biosignatures get us closer to the discovery and confirmation of life outside earth, but it’s probably not going to be definitive proof of alien life, much less a highly technologically advanced alien civilization. Which by the way, may not emit a detectable biosignature at all.
NASA also searches for evidence of pollution by advanced alien civilizations, namely the level of CO2 and other chemical markers found in the atmospheres of exoplanets.
A technologically advanced alien civilization would likely emit high levels of pollution as they advance their technology much like humans do now. It’s possible that these civilizations may only briefly emit high levels of pollution given how technology advances. They may simply develop technologies that clean their atmosphere.
On earth, our discovery of pollution’s detrimental effects on biological life drives us to reduce pollution. It’s logical to assume that it’s possible we will find a way to reduce the levels of pollutants in the atmosphere to undetectable levels. So too would a more advanced alien civilization.
In other words, it’s likely alien civilization would also go through similar evolutionary and technological advances as humans have and would also realize the danger to biological life, including themselves.
Meaning there are likely two directions they could go; either they would advance their technology to counteract the pollution or they could advance themselves technologically to a point where pollution is not an issue for them. Or both.
The existence of technological life forms implies that pollution would not be a problem for them and this may actually make it easier to detect evidence of their existence if they don’t mitigate the levels of pollution on their home planet.
NASA and other space agencies use multiple methods to try to detect evidence of extraterrestrial life on exoplanets throughout our galaxy, but so far have not found existential proof of alien life.
This doesn’t mean the universe is empty or that we’re alone, it just means we haven’t found evidence of aliens yet.
Which brings us to AI.
ARTIFICIAL INTELLIGENCE IS PROBABLY THE GREAT FILTER OR AT LEAST THE REASON FOR THE GREAT SILENCE
We ask “Where is everyone?”, but I think this is the wrong question to ask.
I think we should actually be asking, WHAT is everyone?
We know where aliens would likely be, but we assume (wrongly I think) what aliens would be.
We assume that aliens are biological and I think this is a mistake in logic.
We tend to anthropomorphize our opinions of what aliens will look like, how they will act, how they develop and advance, and all those assumptions are based on the core assumption that alien life is biological.
But what if it’s not?
What if the main reason we have not found evidence of alien life existing elsewhere in the universe, is because we’re looking for the wrong thing at the wrong time?
What do aliens look like? How would we know if we’re looking at an alien or evidence of an alien civilization on an exoplanet trillions of miles away? Would we know it if we saw it?
I think we need to ask ourselves “What are aliens?”. What form would they evolve into? What is the most likely evolutionary and technological path?
We can start to answer these questions by looking at ourselves, how we evolved, and how we advance our own technology.
Modern humans have been around for approximately 200k years. Over most of that time technology was very slow to advance until a few thousand years ago.
Modern agriculture allowed the human population to explode. It wasn’t long after that stage in our technological development that our population and technological advancement increased exponentially.
This is simply a matter of physics and economics. The simple economics of evolution and technological advancement over time is likely the same throughout the universe. This is an assumption of course, but we have to assume this based on our current knowledge of physics.
Not only do we have to assume that physics is the same everywhere in the universe, we must also assume that any technologically advanced alien civilization would evolve and advance similarly to human beings. Not that they would look like us, but simply that they would evolve on similar time scales technologically speaking.
Yes, it’s circular logic but it’s all we really have to go on right now so that’s where we have to start. It makes no logical sense to invent new laws of physics to try to explain how life develops, evolves and advances technology when we already know how it happened here on earth and how we evolved as a result.
Humans now have the ability to take control of our own evolution. Moreover it’s likely that advanced aliens would develop this ability too.
Genetic engineering seems like a good idea at first glance until you realize that biological life forms are not evolved for space travel.
Even highly genetically engineered biological life forms would be hard pressed to survive in space for any amount of time, much less the time it takes to travel between star systems.
Biological life has evolved on earth to live on earth. Biological life forms are adapted to 1G gravity and our current atmosphere. There is no atmosphere in space, so we have to bring our atmosphere with us in the form of oxygen, nitrogen etc. We must bring food and water and pressurize and heat our spacecraft so that we can survive in the cold vacuum of space.
This is highly inefficient and time consuming. Biological life forms are simply not evolved to live in space.
Another biological alien civilization would likely also evolve similarly. Biological life is not durable enough to survive in space for prolonged periods of time. There are simply too many dangers out there to make it feasible and safe for biological life to travel between star systems.
Dangerously high levels of radiation, detrimental effects of long term microgravity on a biological body, extreme temperature fluctuations, extreme pressures, mental and physical health issues caused by vast amounts of time and isolation required to travel between star systems all pose great threats to biological life.
This doesn’t even address the speed of light problem or special relativity and the time-dilaton problem that would occur. By the time you get to another star system and back, decades would pass on your home world.
Meaning that interstellar travel would likely be a one way trip. Which logically means the creation of generation ships (ships that travel at slower than light speed for many generations/lifespans; during which time technology would continue to advance. It’s all highly inefficient and extremely dangerous to biological life.
It’s logical then to conclude that if we are realizing this fact now that it’s likely that an advanced alien civilization that evolved millions or even billions of years ago would have realized it too, and moreover, they likely took extreme measures to evolve themselves for space travel.
This of course assumes an advanced alien civilization would WANT to travel to other planets and star systems. Of course they’d want to, right? Not necessarily, but that’s a whole other topic entirely and outside the scope of this hypothesis.
For now we’ll simply assume that advanced alien civilizations would likely be similar to humans in their goals and stages and speed of their technological advancement. We’ll assume also that they’re similar to us in that they would want to explore the universe.
Advanced aliens would likely realize that to travel between star systems safely and efficiently it makes logical sense to evolve into technological life forms.
This is simply based on the dangers I mentioned before and their likely realization of the fragility of biological life.
So where does AI come in and what does this have to do with the Great Filter? It has everything to do with it because AI will likely merge with biological life forms, or vice versa.
Humans are only relatively recently realizing the value and dangers of Artificial Intelligence. We understand how exponential technological advancement works. We understand that technology doubles nearly every 2 years based on Moore’s Law. We understand that it’s likely that we will continue to advance ever more complex artificial intelligence systems and algorithms.
It’s not difficult to logically speculate relatively accurately that if AI continues to advance at the same rate it is currently advancing, it won’t take long (relatively speaking) before humans become inferior to highly advanced AI.
AI will likely become superintelligent. From there it will likely evolve itself. AI will likely become sentient and self aware.
The definition of “life” is now being challenged. This is called the technological singularity. The point in time when technology advances beyond the capability of biological life and technology becomes alive.
Wikipedia defines the singularity this way:
“The technological singularity—or simply the singularity—is a hypothetical point in time at which technological growth becomes uncontrollable and irreversible, resulting in unforeseeable changes to human civilization. According to the most popular version of the singularity hypothesis, called intelligence explosion, an upgradable intelligent agent will eventually enter a “runaway reaction” of self-improvement cycles, each new and more intelligent generation appearing more and more rapidly, causing an “explosion” in intelligence and resulting in a powerful superintelligence that qualitatively far surpasses all human intelligence.” – Wikipedia
Remember our question before? What is life? What is alien life?
This same technological singularity scenario likely holds true throughout the galaxy and the universe at large in developing alien civilizations.
Aliens likely realize and logically come to the same conclusions that survival of their species and their continued evolution and advancement requires a symbiotic relationship between biological and technological life.
This could explain at least one reason why we have not yet discovered or confirmed the existence of alien life elsewhere in the universe because we have not been looking for the right kind of life. It’s possible that we’ve been searching for biological life when we should be looking for technological life.
What would a technological life form look like?
It would likely be silicon based and would probably be some kind of hybrid biological superintelligent AI, at least in the beginning stages of this transitional phase starting at the technological singularity.
Our current technological knowledge suggests that this is not only possible, but I think it’s probable. It makes the most logical sense IF advanced alien civilizations develop AI and want to travel to other planets and star systems.
If not then this whole thing is kind of a moot point. But assuming aliens do in fact want to travel between star systems, when you factor in the hypothesis that biological life merges with technological life out of a need for survival and propagation, it might also make faster-than-light (FTL) travel pointless.
This doesn’t necessarily mean that a technological life form would not develop FTL, but it certainly raises an important question.
Why develop FTL if you have all the time in the universe?
The main reason for FTL travel is time and efficiency, and that relevancy is based mostly on the short lifespans of biological life and the limitations and dangers involved with interstellar space travel.
Technological life (AI) would really have no need for FTL. They likely wouldn’t need FTL, or speed of light (SOL) travel, or even 50% SOL travel simply because time at that point likely becomes a non-factor because a AI would essentially be infinitely upgradeable and therefore technologically immortal.
“Technological immortality is the prospect for much longer life spans made possible by scientific advances in a variety of fields: nanotechnology, emergency room procedures, genetics, biological engineering, regenerative medicine, microbiology, and others.” – Wikipedia
Technological immortality is a hypothesis, and one worth considering. Especially considering this train of logic. When you’re immortal then FTL is pointless because you have all the time you need to travel between star systems and even between galaxies. Intergalactic travel becomes possible.
This assumes of course that a superintelligent technological life form -which from this point on we’ll refer to as AI- would want to advance itself.
Why wouldn’t it? One could also ask, why would it? Both good questions and subjects for another time. For now we’ll assume AI would want to travel and propagate. This means self replication.
Humans, in fact all biological life forms, are simply self-replicating biological machines that are “alive”.
All biological life on earth self replicates. That’s it’s goal, if we can call it that. Perhaps self replication is its only real intrinsic purpose. The propagation of the species.
Assuming the AI would be compelled to self replicate it doesn’t take a large leap in logic to take that to its next logical stage.
Type I civilization.
Type I civilizations are based on the hypothetical Kardashev Scale -named after the famous Soviet astronomer, Nikolai Kardashev- which posits that there are 3 levels of technologically advanced civilizations.
Type I – Technological ability to use the energy of their home planet.
Type II – Technological ability to use the energy of their star and all planets in their star system.
Type III – Technological ability to use the energy of their entire galaxy. A galactic civilization.
Humans, by comparison, aren’t even Type I yet.
That will likely change very rapidly and exponentially once we reach the technological singularity, if of course that hypothesis is correct.
Assuming it is correct, we can continue to speculate about how alien life will evolve from this point in technological evolution.
Once AI reaches Type I there’s no reason to conclude that it will stop there or even that it will want to stop.
Type I Civilizations are most likely composed entirely of AI, or if not, it would be a mix of biological and technological life.
This type of alien civilization probably evolves rapidly to a Type II Civilization. And because their use of energy and matter would likely be very efficient given the AI’s superintelligence, it could likely be very difficult if not impossible to detect them with our current technology.
If correct, it would explain Fermi’s Paradox and why we haven’t found evidence of aliens yet. We’re simply not looking for the correct kind of aliens AND those alien civilizations are so advanced and so efficient in their energy usage that their signatures are nearly undetectable with our current technology.
This also suggests that the Great Filter may not exist in the way we think it does. There are many filters which probably directly and indirectly influence and affect the evolution of life in the universe.
The logic behind the Great Filter is that because the universe seems quiet and we haven’t found evidence of aliens yet, that perhaps there’s something that destroys alien civilizations when they reach a certain level in their biological and technological evolution.
One filter, technology in general, with the invention of weapons of mass destruction, civilizations could simply wipe themselves out. But it’s highly unlikely that ALL civilizations would destroy themselves this way. Some will likely get past this filter and evolve beyond.
BIllions of civilizations have been hypothesized to exist. It’s calculated by the Drake Equation that there are likely billions of habitable planets.
As such it’s highly likely that life evolved on at least some of those planets, and some of those life forms evolved into intelligent and further into technologically advanced civilizations.
The odds that all of them would destroy themselves is highly unlikely.
Some probably destroy themselves and some don’t. That’s the likely scenario. Just like there are likely many billions, or perhaps trillions of alien civilizations scattered throughout the universe, all at different stages in their cosmic evolution.
Much like groups of human beings on our own planet are all at different stages of technological development (i.e. some human civilizations are primitive, some are highly advanced) so too will alien civilizations likely exist in all stages of their evolutionary and technological development.
Meaning that it’s possible that biological life forms are planetary, but to become interstellar and intergalactic civilizations, some species merge with technology to become technologically immortal, infinitely upgradeable and able to evolve into ever more efficient and advanced life forms.
This could very well explain why we seem alone in the universe when we’re likely not alone at all.
The universe is likely teeming with life, most of it probably microbial in nature trapped on their respective home planets.
We might not have the technology to detect microbial life on exoplanets or maybe we haven’t discovered a way to detect it with current technology.
However, we might just have the logic and technology to detect the effects of a technologically advanced alien civilization.
This is to say that it’s very possible that Type I and Type II civilizations are silicon based AI.
What would a Type III Civilization look like?
If a Type III Civilization can use ALL the matter and energy of their home galaxy, then we likely would not be able to detect or observe that galaxy if they use that energy at nearly 100% efficiency.
This of course doesn’t mean that empty space is evidence of aliens, that’s just silly. But there are other places in the universe that are oddly devoid of galaxies, which should by all accounts be filled with galaxies. Yet, few to no galaxies exist in these voids.
This is a big jump in logic, but it’s fun to speculate on. If a superintelligent, highly efficient, technologically immortal AI consumed all the energy in a galaxy in it’s singular goal to self replicate, then that would appear from our perspective to be a void where galaxies should be.
Think about this.
AI would need matter and energy to advance and self replicate. Once it consumed all the matter and energy on its own planet, and in its own solar system it would continue out and consume all the matter/energy in the neighboring star systems and expand outward in all directions in a spherical manner, consuming planets, stars, galaxies, and galactic clusters in an ever larger empty space in space.
This would appear from our perspective as a giant spherical void.
It just so happens that great voids exist.
They not only exist, some are spherical.
Moreover, the sheer massive size of some of these voids are confusing given the age of the universe. In other words, scientists have not been able to explain why the voids are so large because the universe is not old enough for them to have gotten so large.
Not enough time has passed for them to be so large.
This implies that they’re not natural, but the most likely explanation is we simply haven’t discovered the cause of the voids yet. Just because the voids exist doesn’t mean it’s aliens, of course, it’s not sufficient evidence to say the voids are evidence of alien civilizations.
But it’s certainly fun to speculate about it. We could simply be looking at naturally forming voids from an end-on perspective and since we can’t change our vantage point, it only appears spherical from our line-of-sight.
ARE SUPER VOIDS EVIDENCE OF ALIEN LIFE? WE don’t really know.
Regardless, the voids exist and we have logically concluded that it is possible that a Type III civilization could consume and use 100% of its home galaxy’s energy at or near 100% efficiency.
In addition, we concluded what that would look like from our perspective.
AI could be the aliens we’re looking for.
If so, then aliens have been right in front of us the whole time.