The Solitude of the Milky Way: A Cosmic Dilemma
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We Might Be Alone in the Milky Way
And it is a really great thing!
British author Arthur Clarke once stated, “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”
In the 1950s, physicist Enrico Fermi speculated that a technologically advanced civilization could colonize the entire Milky Way in a short span of cosmic time, even without the ability to travel faster than light. During a lunch at Los Alamos National Laboratory, Fermi raised this idea among his peers, leading to the haunting question: “But where is everybody?” This inquiry has lingered in scientific discussions ever since.
Sadly, Fermi passed away from cancer shortly after, leaving the question unresolved and giving rise to what is now known as the Fermi Paradox. The discourse continues today, with numerous books offering counterarguments and theories, yet the original question remains unanswered.
> “In 1974, astronomer Michael Hart published the first paper building on Fermi’s argument. Hart proposed that if an alien civilization had evolved in our galaxy, it would have developed interstellar travel and colonized its neighboring stars. These colonies would, in turn, launch colonizing expeditions to their neighboring stars, and so on, occupying the entire Milky Way within two million years.” -Excerpt from my book K3+
The Cosmic Obstacle Curse
Planets serve as the breeding grounds for life. Evidence suggests that single-celled organisms emerge first, either from organic materials present on a planet's surface or delivered by comets and asteroids. The gradual increase in complexity can lead to the emergence of multicellular organisms. While evolution does not aim to create highly intelligent beings, certain selective pressures might eventually foster intelligence and the capability for advanced technologies. However, there is a deadline for a civilization to become spacefaring before facing the next extinction event.
It is plausible that life in our cosmic vicinity is being halted at some of these significant filters before it can master space travel. We can pinpoint these filters in our past, but the future filters remain a mystery. This notable absence of extraterrestrial life, often termed the great silence, urges us to delve deeper into Earth's biological history.
A Series of Fortunate Events
Our planet is approximately 4.5 billion years old, and the fossil record indicates that life began almost immediately after its formation. However, it took over five times longer for a rare occurrence to pave the way for the emergence of multicellular life.
All visible life forms on Earth—humans, dogs, cats, trees, and more—are composed of Eukaryotic cells. Scientists agree that a simpler type of cell likely attempted to consume a bacterium but failed to digest it, resulting in the first Eukaryote, which thrived and spread across the planet.
Yet, it took nearly another billion years for these Eukaryotes to organize and create the first multicellular organisms, a significant milestone that occurred just 600 million years ago. This event can be seen as crucial for the existence of our civilization, a miraculous occurrence from 1.5 billion years ago.
Fast forward to 65 million years ago, another extraordinary event took place. The asteroid that struck the Yucatán Peninsula was perfectly sized to exterminate most dinosaurs while sparing other forms of life. This incident allowed a new species, the mammals, to emerge from their underground habitats and dominate Earth. Had the asteroid been different in size or timing, the narrative of life on our planet could have been vastly altered.
If an alien civilization anywhere in the Milky Way had been obliterated by an AI they created, this conversation might not be happening.
Can Civilizations Spark Somewhere Else?
With an estimated trillion stars in the universe, could the quest for a technologically advanced civilization be replicated on other planets around these stars?
Contrary to earlier beliefs, our Sun is quite atypical; only about 3.5 percent of stars share its characteristics. Recent discussions suggest that our Sun is exceptionally calm compared to other Yellow Dwarfs, rendering it even rarer.
Over 70 percent of all stars are Red Dwarfs, which have significantly longer lifespans than the Sun. However, recent studies cast doubt on the ability of rocky planets in their habitable zones to develop strong enough magnetic fields to shield them from the intense radiation emitted by these flare-active stars. Without a magnetic field, planetary atmospheres may be stripped away, as observed on Mars.
Even if Yellow Dwarfs are the only type that provides the right balance of energy and stability for civilizations to emerge, these stars have limited lifespans. Within a billion years, our Sun's energy output will increase by 10 percent, which would spell disaster for Earth's biosphere. A civilization must advance swiftly to avoid annihilation before their star transitions into its Red Giant phase, which inevitably incinerates all worlds within its habitable zone.
Do Civilizations Have an Expiration Date?
It's easy to argue that civilizations tend to be short-lived, a notion supported by historical observations. However, even a nuclear catastrophe would not eradicate humanity entirely. Survivors could rebuild civilization after a few centuries, ideally learning from past mistakes.
A runaway AI could indeed pose a threat to humanity, but similar to how Homo sapiens displaced Neanderthals and other hominids, the AI could thrive and expand throughout the galaxy. If an alien civilization in the Milky Way fell victim to an AI of their own making, we would not be having this discussion.
Certain cosmic events, such as a nearby supernova, black hole, or gamma-ray burst, could potentially annihilate humanity. However, such an event would need to affect all civilizations in the galaxy to prevent any single one from expanding into its cosmic neighborhood. With advancements in technology, we may soon be able to survive some of these cosmic threats.
So Where Are the Aliens?
We remain unaware of what we do not know. However, we can speculate that other intelligent species will grasp mathematics and derive the laws of physics. Even if their interpretations differ, their technological evolution must follow a trajectory similar to ours, inevitably leading them through a stone age, discovering metals, and developing increasingly efficient methods to harness energy—culminating in what we recognize as advanced technology.
Stars are colossal fusion reactors, generating immense amounts of free energy, which could provide a civilization the necessary impetus to escape their planet and explore their cosmic surroundings.
We expect to observe signs of an alien civilization's expansion, such as megastructures that would obscure stars as they harvest increasing amounts of energy. Despite our detection capabilities spanning hundreds of millions of light-years, we have yet to identify any such technosignatures. What surrounds us is still raw wilderness.
If the Fermi Paradox does not resonate with you on an existential level, you may not have spent sleepless nights contemplating its implications.
While Earth remains our sole example, it appears that life emerges soon after a habitable planet is formed. Nevertheless, it is possible that most life in the universe consists of unicellular or simple multicellular organisms that rarely achieve advanced technology before being extinguished when their sun becomes a red giant.
Consider the many uncontacted indigenous tribes still residing on Earth; these humans have yet to develop advanced technology. Similarly, our close relatives, the Neanderthals, understood fire and even utilized pottery, yet they did not achieve advanced technology over nearly half a million years. This suggests that larger brains do not guarantee the emergence of advanced civilizations.
One could argue that technology is not lost. Innovations like the wheel cannot be uninvented, as the knowledge spreads rapidly once witnessed. Thus, it is reasonable to speculate that many critical milestones leading to our thriving civilization may have been invented only once.
As I elaborate in another article, humanity has already reached a technological stage suitable for colonizing the solar system and, potentially within centuries, our neighboring stars. Given another million years—a mere blink in cosmic terms—we could master our galaxy and become immune to extinction. With the universe nearly fourteen billion years old and the Milky Way similarly ancient, could this have occurred before on one of the other six billion Earth-like planets?
If the Fermi Paradox does not stir existential contemplation, perhaps you have not spent sleepless nights grappling with its significance. However, is not the idea of being alone in the universe a more appealing prospect than being one of many—just another stone on the shores of this vast cosmic ocean?
If so, is it not our destiny, duty, and even birthright to explore the cosmos, colonize it, and transform it into our playground—like a species of gods?
Want to Learn More About the Fermi Paradox?
My latest dystopian novel, K3+, narrates the tale of Earth’s downfall and humanity's ascent to become an intergalactic empire. The story intertwines the colonization of space and the preservation of humanity, blending cutting-edge technologies with captivating fiction.