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10 Reasons That We Still Haven’t Found Aliens

by S. Grant
fact checked by Jamie Frater

The Fermi Paradox, first introduced by physicist Enrico Fermi, asks the question, “Where is everybody?” Or, more specifically, “Where are all the aliens?”

SEE ALSO: 10 Times We Thought We Had Found Proof Of Aliens

When we factor in the size of the universe, the number of Earth-like planets, and a range of other variables (as outlined in the Drake equation), there should be tens of thousands or more extraterrestrial civilizations in the galaxy. And with the galaxy being around 10 billion years old, scientists say that intelligent worlds have had plenty of time to contact one another. So if aliens should statistically exist, why haven’t we encountered any yet?

10Earth Is Special

The Rare Earth Hypothesis suggests that the chain of events that created life on this planet was so complex that only a biological perfect storm could recreate it elsewhere. While there may be Earth-like planets, none of them have exactly what it takes for intelligent life to develop. In other words, we haven’t met any aliens, because none are out there, or they are so few and far between that contact is highly improbable.

The major factor that makes Earth so hospitable to life is its long period of relatively stable climatic conditions, which is due to the planet’s unique orbit and position. Without our precise distance from the Sun and Moon, the planet would likely be too hot or cold, have too little oxygen, and be too unstable to support any life beyond bacteria.

Paleontologist Peter Ward and astronomer Donald Brownlee were the first to introduce the Rare Earth Hypothesis. Even though nearly 15 years have passed since they publicized the theory, and Earth-like planets have since been detected, they are still confident that the odds of those worlds having life are extraordinarily low.

9All Intelligent Life Hits A Stumbling Block

According to the Great Filter theory, alien life does exist, but intelligent life is incapable of technologically advancing enough for long-distance space communication or travel. Although our modern spaceships, satellites, and radios may make it seem like we’re getting closer, we’ll inevitably reach a barrier or catastrophe that will either wipe us out or cause technology to devolve.

We know cataclysmic natural disasters periodically strike Earth, so it’s possible that these types of events hit worlds everywhere, sending intelligent life back to the Stone Age before technology can adequately develop. Or, maybe we annihilate ourselves, such as through nuclear war. Whatever the filter is, it seems to mean nothing but bad news for humans. Not only will we never communicate with space beings—we’ll probably die trying.

However, there is one possible bright side. Some think that we are the first individuals to make it past the filter, so we’ll eventually be the first super-intelligent beings to roam space.

8They’ve Moved Out Of The Universe

According to futurist John Smart’s Transcension Hypothesis, intelligent alien life once existed in our universe, yet it became so advanced that it moved on to greener pastures. More specifically, aliens became so evolved that they stopped looking at outer space and instead focused on inner space.

The concept can be compared to the miniaturization we’ve experienced in computers. What initially began as an enormous, room-filling technology progressively became smaller (even pocket-sized) while simultaneously growing in complexity and power. To Transcension supporters, intelligent life evolves in much the same way, constantly working toward a denser, more efficient use of space, time, energy, and matter (“STEM compression“). Eventually, we’ll be living and operating at the nano-scale until we become so small that we create and exist in a black hole outside this space-time continuum.

To Smart and others, black holes are the ultimate destination. They allow for ideal computing and learning, time travel, energy harvesting, and more. Civilizations that don’t achieve this destiny are failures.

Other cosmic beings may be working toward their own transcendence. Like humans, they might emit space broadcasts, but these types of signals are supposedly the work of immature civilizations and are unlikely to be successful. Also, based on Moore’s Law (that computing power doubles every two years), these beings would likely reach transcendence before exploring the cosmos.

7Earth Isn’t As Great As We Think

Perhaps it’s hubris to think that aliens would even have an interest in us or our planet. Worlds far more interesting and life-supporting may exist, and intelligent beings would much rather spend their time focusing on super-habitable places rather than Earth. This theory is the complete opposite of the Rare Earth theory—Earth isn’t special at all.

An alien race capable of traveling or communicating across light years would no more care about chitchatting with us than a human would converse with a fly. Likewise, they’d undoubtedly have their own superior technologies and would not require any of our measly resources. If, however, they did need to harvest minerals or elements, they wouldn’t have to visit Earth. Those things are found floating all over space.

Furthermore, no matter how intelligent the beings, traveling across light years is no easy feat. What are the odds they’d invest all that energy coming here when there are 8.8 billion Earth-like planets in the Milky Way? For followers of this theory, to think Earth is everyone’s destination is to suffer from the same geocentrism that led to Galileo’s erroneous persecution.

6We’re Living In A Virtual Reality

Arguably one of the most difficult to accept explanations to the Fermi Paradox is the Planetarium Hypothesis. Our world is a “form of virtual reality ‘planetarium,’ designed to give us the illusion the universe is empty.” We haven’t discovered any extraterrestrial life because those extraterrestrials haven’t designed that into the program.

The fundamentals of this theory date back to Descartes, who asked, “How can we know that the world around us is real—are we just a brain in a vat, which thinks it’s living in the real world?”

Instead of being brains in a vat, however, most modern supporters of this notion think we’re in a computer simulation designed by advanced aliens. These aliens are capable of harnessing enough energy to manipulate matter and energy on galactic scales. Why would the aliens want to watch us like ants in a farm? Maybe just for fun, or maybe they just made us to see if they could.

As unlikely as the Planetarium Hypothesis may sound, professional philosophers and physicists are serious about this idea. They say that we’re more likely to be artificial intelligences in a fabricated world than to have our own minds. Furthermore, we will likely discover the simulation, since we’ll inevitably notice a glitch in the system or devise an adequate test to prove the theory.

5We Live In The Cosmic Boonies

Although intelligent alien life might exist, our planets may be too far apart to make communication practical or purposeful. Earth may be so far away from other inhabited planets that we’ve simply been overlooked. If that doesn’t feel lonely enough, some claim most other worlds exist relatively close together in clusters and are interacting with each other, while we’re off in cosmic no-man’s-land missing out on the party.

The roots of this idea come from a mathematical theory known as percolation, which describes how things clump in a random environment. Based on the percolation theory, the universe naturally formed with areas of large clustered growth and a few smaller areas of growth in outlier positions. Other intelligent beings are in the big cluster, and Earth is an isolated outlier.

Instead of trying to make contact with these faraway beings, some, like Stephen Hawking, suggest that we continue to lie low. Hawking says that if we pick up on an alien signal, “We should be wary of answering back, until we have evolved.” Otherwise, we may suffer a fate akin to the Native Americans after Columbus arrived.

4We Haven’t Spotted Their Signals (Yet)


Photo credit: Dave Deboer

Scientists like Frank Drake and the late Carl Sagan have argued the “absence of evidence is very different from evidence of alien absence.” Alien hunting has been held back by lack of government funding, which is necessary to afford extensive alien-tracking equipment and resources. Historically, the search for extraterrestrial intelligence (SETI) programs have had to rely on borrowed radio telescopes and other equipment, which they could only use for a limited time. These hindrances have made it virtually impossible to make any real progress.

Still, there is some good news—at least for those who think making alien contact is a good idea. The Allen Telescope Array, a radio telescope array specially designed to search for extraterrestrial intelligence, became operational in 2007. This mega-telescope (consisting of 42 individual 6-meter-wide (20 ft) telescopes) was largely funded by Microsoft co-founder Paul Allen. After numerous setbacks, it finally seems ready to begin doing some serious space exploration. If anything on Earth is capable of picking up alien signals, this is the device.

3We Can’t Recognize Their Signals

Even if other planets are hospitable to life, would the beings there evolve similarly to living things on Earth? Maybe they are so different that neither of us would recognize a signal from the other. Comparable to how bats visualize sound waves while we only see light, it’s possible that humans and aliens operate with entirely different senses.

As cosmologist and astrophysicist Lord Rees pointed out, “They could be staring us in the face, and we just don’t recognize them. The problem is that we’re looking for something very much like us, assuming that they at least have something like the same mathematics and technology. I suspect there could be life and intelligence out there in forms we can’t conceive.”

Things get especially tricky when trying to connect with a highly advanced race because they might use communication methods (such as neutrinos or gravitational waves) beyond our technological understanding. Likewise, our primitive radio emissions might look like nothing more than white noise to them. If aliens and people are indeed extremely unalike, it’s unlikely that we’ll ever make contact and solve the Fermi paradox—especially so long as we’re anthropomorphizing aliens and expecting them to communicate as we do.

2Super-Organisms Are Inherently Suicidal

The Medea Hypothesis, coined by paleontologist Peter Ward, is the notion that humans and other super-organisms carry within themselves the seeds of self-destruction. In this way, it very much ties in with the Great Filter theory, since it suggests that we end up dying before evolving enough to make alien contact.

The hypothesis is named after the murderous Medea from Greek mythology, who killed her own children. In this case, the planet is Medea, and all living things are her offspring. We don’t want to die, but Mother Earth made us destined to kill ourselves. Extinction is built into our biology to ensure that we are eliminated before we create too much of an imbalance on Earth. Once humans become an incurable plague on the planet, we will do something to guarantee our own demise.

Ward believes that almost all previous mass extinctions were brought on by living organisms. For instance, he blames the two Snowball Earth periods from millions of years ago on plants that proliferated so wildly that they absorbed excessive amounts of CO2. This brought about global cooling and consequently the plants’ demise. Similarly, if humans really are the root of today’s climate change, we may be well on the way to guaranteeing that our own species can’t survive on the planet.

In short, our internal suicidal clock will run out long before we get the chance to connect with aliens.

1They Walk Among Us

It sounds like science fiction, yet people in prominent positions are confident that aliens live and work all around us. For example, former Canadian defense minister Paul Hellyer gave an interview in 2014 in which he claimed that 80 different species of alien life live on Earth. Some of them (including Nordic blondes) look nearly identical to humans. Another group, the “Short Greys,” appear more like stereotypical aliens and stay relatively hidden from the general population.

Hellyer is not alone in his claims. Physicist Paul Davies from Arizona State University and Dr. Robert Trundle from Northern Kentucky University have similar opinions about the existence of aliens on the planet. To Hellyer, Davies, Trundle, and those who share their beliefs, the Fermi paradox has already been answered—aliens do exist, and whether humans realize it or not, they interact with us on a daily basis.

Despite experiencing a great deal of criticism from their peers and the public, these men continue to be outspoken in their opinions.

fact checked by Jamie Frater