The Fermi Paradox – Where Are They?

The Fermi Paradox refers to the striking contradiction between current estimates, suggesting the likely existence of extraterrestrial civilizations and the absence of any direct evidence or contact with such civilizations. How can this paradox be explained?

The universe is staggeringly vast, containing at least hundreds of billions of galaxies, each varying in size and structure. Galaxies can range from having just a few thousand stars, as seen in Segue 1,¹ to as many as 100 trillion stars (IC 1101²). Our own galaxy, the Milky Way, is home to approximately 200 billion stars. A significant number of these stars are believed to have planets, with over 5,000 confirmed so far. Estimates suggest that the Milky Way alone may harbour up to 10 billion planets similar to Earth, orbiting within the ‘habitable zone,’ where conditions could be suitable for life as we know it.³ These planets are considered promising candidates for the existence of extraterrestrial life.

Thus, it would appear that the universe should be teeming with various forms of life, including intelligent life. Scientists are also investigating the possibility of extraterrestrial life within our own Solar System. The reasoning behind this is as follows: if life on Earth originated 3.6 billion years ago—roughly 1 billion years after the formation of the Solar System—and if life could have emerged elsewhere within the Solar System,⁴ this would suggest that life arises relatively easily. In other words, it should be widespread throughout the universe.

What is the Fermi Paradox?

Scientists have yet to find any evidence supporting the existence of even a single extraterrestrial civilization. The search for extraterrestrial civilizations, conducted under the SETI project (Search for Extra-Terrestrial Intelligence), has thus far been fruitless. As early as the 1950s, scientists began to question why no extraterrestrial beings had been discovered. In 1950, while having lunch with his colleagues and discussing the possibility of extraterrestrial life, the Italian theoretical and experimental physicist Enrico Fermi (1901-1954) famously asked, ‘Where are they?’.⁵ This enormous discrepancy between modern scientific predictions regarding the prevalence of extraterrestrial life and the lack of empirical success in this area is known as the Fermi Paradox.

The Fermi Paradox can be summarized as follows:

The size and age of the universe suggest that many technologically advanced extraterrestrial civilizations should exist. However, this reasoning is contradicted by the lack of observational evidence for their existence. Thus, either the initial assumptions are incorrect and technologically advanced life is far rarer than believed, or observation methods are incomplete and humanity hasn’t detected them yet, or the methods are flawed, and humanity is searching for the wrong signs.⁶

Enrico Fermi had a clear understanding of the problem at hand. Today, it is accepted that the universe is 13.7 billion years old, with our Solar System having formed 4.6 billion years ago. The oldest stars in our galaxy are thought to be approximately 13.4 billion years old, and the galactic disk is estimated to be between 10 and 12 billion years old.⁷ This timescale is certainly long enough for our galaxy to have become full of extraterrestrial life. Furthermore, Fermi was correct in assuming that at least some alien civilizations would be as curious as we are. As a result, they would likely engage in interstellar travel or, at the very least, send signals similar to the Arecibo message of 1974.

Theoretical Calculations

If such a civilization were to emerge and avoid its own extinction, it could potentially spread throughout our galaxy at a remarkable pace. Fermi proposed that, assuming the first interstellar journey took the aliens one million years (using generation ships), the number of colonies would double every subsequent million years. After 10 million years, there would be 1,023 colonies in addition to the original civilization. After 20 million years, the number of colonies would reach one million, and after 40 million years, it would swell to one trillion. This figure is close to the estimated number of planets in our galaxy. In other words, within a few tens of millions of years, the galaxy would become overwhelmingly populated.

For context, the current Guinness World Record for the fastest spacecraft speed is 163 km/s.⁸ It is simple to calculate that, at this speed, a spacecraft from Earth would reach the nearest star, the Proxima Centauri, in around 8,000 years—far shorter than the one million years Fermi had anticipated.

The Kardashev Scale

Interestingly, there are also more optimistic estimates for the potential conquest of space, which assume overcoming the speed of light barrier. Take, for example, the Kardashev scale.

Nikolai Kardashev (1932-2019) was a Russian astrophysicist and radio astronomer who created a theoretical scale for the development of cosmic civilizations based on their ability to use the energy of celestial bodies. He divided cosmic civilizations into several types:

• Type I civilization – capable of utilizing all the energy of its home planet (in our case, Earth),⁹
  
• Type II civilization – would use all the energy of its home star (in our case, the Sun) and be capable of extensive interstellar travel,
  
• Type III civilization – would be able to use the energy of an entire galaxy (in our case, the Milky Way).¹⁰
  

Kardashev claimed that our civilization could reach Type I status in a few hundred years (Freeman Dyson estimated about 200 years), Type II in 3,200 years, and Type III in 5,800 years.¹¹ It is important to note that the diameter of our galaxy is approximately 100,000 light-years. In other words, these scientists propose that cosmic civilizations would likely discover methods to surpass the light-speed barrier, such as by utilising Alcubierre drives.¹²

Regardless of the scenario, a cosmic civilization could potentially colonize our galaxy within a timeframe of a few thousand to several tens of millions of years. Even in the most pessimistic case, this would be hundreds of times shorter than the estimated age of our galaxy.¹³ Moreover, if we assume that these civilizations have found ways to overcome aging and death, the galaxy would become even more densely populated.

They Are Nowhere To Be Found…

All of the aforementioned theoretical considerations are overshadowed by one simple fact: we have yet to find any evidence of cosmic civilizations. Various explanations have been put forward to account for this absence. Some argue that all extraterrestrial civilizations have already perished; others suggest that they do exist, but our technology is too rudimentary to detect them. Still others propose that cosmic civilizations are common in our galaxy, but intentionally keep our planet in a kind of cosmic reserve.¹⁴ All of these explanations have their weaknesses.¹⁵

However, there are other, more plausible possibilities. Firstly, extraterrestrial civilizations may indeed exist but are currently sparsely distributed across space. Secondly, as pessimistic as it may sound, we may simply be alone in the universe. Determining the true state of affairs is challenging, as our current data is insufficient. Nevertheless, both possibilities imply that the universe is, in fact, young, as the Bible suggests.¹⁶ If the universe were truly billions of years old, and if even one extraterrestrial civilization had colonised the Milky Way millions of years ago, we would almost certainly be aware of their presence by now. This illustrates the Fermi Paradox, as the young age of the universe helps explain why we have not yet discovered any extraterrestrial civilizations.

By the way, we recommend reading the articles:

• What Do Astronauts Have To Say About God?
• Are There Planets Better Suited for Life Than Earth?
• Which Came First: The Flood or the Pyramids?
• The Origin of Viruses: Three Possible Variants
• The Mythology and Origins of Dragons Across Cultures – Part 1
• Legends of Dragons from Around the World and Their Origins – Part 2

Footnotes

1. Siegel, E. (2020) The Smallest Galaxy Ever Discovered Demonstrates The Unequivocal Need For Dark Matter, Forbes, 6 April. Available from: https://www.forbes.com/sites/startswithabang/2020/04/06/the-smallest-galaxy-ever-discovered-demonstrates-the-unequivocal-need-for-dark-matter/?sh=4e546230354a.
2. Constellation Guide: IC 1101, available from: https://www.constellation-guide.com/ic-1101/.
3. McFall-Johnsen, M. (2019) There Could Be Up to 10 Billion Warm and Cozy Earth-like Planets in Our Home Galaxy, New Research Reveals, Insider, 16 August. Available from: https://www.businessinsider.com/10-billion-earth-like-planets-in-milky-way-galaxy-2019-8?IR=T.
4. Discussion on Mars, Jupiter’s moon Europa, and Saturn’s moons Titan and Enceladus.
5. O’Callaghan, J. (2021) What is the Fermi Paradox?, Live Science, 7 December. Available from: https://www.livescience.com/fermi-paradox.
6. Poszukiwanie cywilizacji w kosmicznej głębi. Paradoks Fermiego trzyma się mocno (2020), Space24.pl, 9 September. Available from: https://space24.pl/nauka-i-edukacja/nasluch-kosmicznej-glebi-w-poszukiwaniu-zycia-paradoks-fermiego-trzyma-sie-mocno.
7. Wethington, N. (2008) How Old is the Milky Way?, Universe Today, 4 December. Available from: https://www.universetoday.com/21822/age-of-the-milky-way/.
8. Guinness World Records: Fastest Spacecraft Speed, available from: https://www.guinnessworldrecords.com/world-records/66135-fastest-spacecraft-speed.
9. Statement on Carl Sagan’s belief regarding Earth’s civilization’s Kardashev scale level at 0.73.
10. A discussion of extended Kardashev scale including Type IV civilization.
11. Kaku, M. The Physics of Extraterrestrial Civilizations, available from: https://mkaku.org/home/articles/the-physics-of-extraterrestrial-civilizations/.
12. A description of the theoretical Alcubierre drive requiring enormous amounts of energy.
13. The Fermi Paradox, SETI Institute, available from: https://www.seti.org/fermi-paradox-0.
14. Wikipedia: Fermi’s Paradox, available from: https://en.wikipedia.org/wiki/Fermi_paradox.
15. A hypothesis regarding the space reserve (zoo hypothesis) and potential space dissidents.
16. Bates, G. (2016) The Fermi Paradox, “Creation”, vol. 38, no. 4, pp. 53–55. Available from: https://creation.com/fermi-paradox.

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Evolution of Thinking - Sebastian S.

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