Reconciling the Drake Equation and the Fermi Paradox, Pt. I

the tl;dr version

It is important to note that Fermi himself never made any official statements nor wrote on the topic of ET. The only way we know about what Fermi said is through physicist Eric Jones, who took statements from 3 people present at that famous lunch in 1950 where Fermi first presented the question of, where are all the aliens? Since Fermi passed away in 1954, it is only from the words of these three that we come to know the so-called paradox: Emil Konopinski, Edward Teller, and Herbert York.

York seemed to have had the clearest memory, recalling of Fermi:

“… he went on to conclude that the reason that we hadn’t been visited might be that interstellar flight is impossible, or, if it is possible, always judged to be not worth the effort, or technological civilization doesn’t last long enough for it to happen.”

Robert H. Gray, The Fermi Paradox Is Not Fermi’s, and It Is Not a Paradox

Therefore, Fermi’s skepticism is not in whether intelligent aliens exist, but perhaps is rooted in the possibility of interstellar travel, or whether a civilization can reach maturity to enable such means. After all, Fermi made his statements in 1950, when rocketry was in its infancy and post-advent of the atomic bomb which he had a hand in creating, giving weight to his observations that interstellar travel seemed unlikely, and the likelihood that an advanced civilization would destroy itself before such feats as interstellar travel came to fruition.

“The Fermi paradox might be more accurately called the ‘Hart-Tipler argument against the existence of technological extraterrestrials’, which does not sound quite as authoritative as the old name, but seems fairer to everybody.”

Robert H. Gray, The Fermi Paradox Is Not Fermi’s, and It Is Not a Paradox

To add further to this confusion, Fermi’s question was not known as a paradox until 1977, when physicist David G. Stephenson used the phrase in his paper, citing astronomer Michael Hart’s 1975 idea that if “they are not here, then they do not exist” as a possible answer to “Fermi’s paradox”. Later, in 1980, physicist Frank Tipler also cited Hart’s paper to suggest that only a self-replicating constructor with at least a human-level intelligence would be able to colonize the stars. Tipler said that because humans did not create these devices already, then it was very unlikely that any other intelligences populate the galaxy, perhaps even the Universe. Obviously, these ideas are a long shot from Fermi’s original notion that intelligent aliens haven’t visited nor made contact with us simply because they do not have the means or perhaps died out before they got the chance. The unknown variable we have yet to investigate (officially, as it were) is whether interstellar travel is possible in the first place, and so, there is no “Fermi’s paradox”.

“In the 1970s astronomers Frank Drake and Carl Sagan devised a method, now called the Drake Equation, for estimating the number of advanced civilizations that might be present in our galaxy. In 1974, Sagan used the method to estimate that a million advanced civilizations might exist in the Milky Way galaxy alone. However, many discoveries in both astronomy and geology have been made since Sagan did that estimate, and these lead to a more pessimistic conclusion.”

John G. Cramer, the Rare Earth Hypothesis

University of Washington’s John G. Cramer has done a thorough analysis of his colleagues’ work, the Rare Earth Hypothesis, devised by the geologist Peter Ward and astronomer Don Brownlee, who together reformulated the Drake Equation according to more recent geological and astronomical discoveries. The Rare Earth Hypothesis makes the argument that our galaxy is mostly devoid of complex life, but rather sparsely populated with planets whose orbits are too close or too far, orbiting stars that are too hot or cold to support the development of life, let alone multi-cellular life. According to Ward and Brownlee, we can expect to find an abundance of bacterial life in the universe, while anything else, especially planets like ours and thus intelligent life, will be exceptional and rare, if impossible to find. As Cramer has explained it, deep freezes and the action of plate tectonics are two unique key features of the Earth that have allowed for complex life to evolve here, making the hypothesis all the more likely to be true.

N = N × fp × fpm × ne × ng × fi × fc × fl × fm × fj × fme*

Here, N is the number of stars in the Milky Way galaxy, fp is the fraction of stars with planets, fpm is the fraction of planets that are metal-rich, ne is the average number of planets in the star’s habitable zone, ng is the number of stars in the galactic habitable zone, fi is the fraction of habitable planets where life does arise, fc is the fraction of planets where complex metazoans arise, fl is the fraction of the total lifetime of the planet that is marked by the presence of complex metazoans, fm is the fraction of planets with a large moon, fj is the fraction of solar systems with Jupiter-size planets, and fme is the fraction of planets with a critically low number of extinction events.

John G. Cramer, The Rare Earth Hypothesis

It is also important to avoid looking too closely at the centers of galaxies, including our own, because these areas contain supermassive stars that are densely packed and often experience supernovae, which could have devastating effects on neighboring stars. Additionally, the elements necessary for complex chemistry, a requirement for life as we know it, are less common in the centers of galaxies. This means we must look towards the larger, more dispersed regions of galaxies for the possibility of life. However, this brings up the issue of distance and time. The nearest galaxy to ours is 179,000 light-years away, and even our own Milky Way is 100,000 light-years across. This means that if other planets developed life and it evolved at a similar pace to ours, we would only just now be receiving signals from those approximately 100 light-years away. Similarly, even if a civilization was advanced enough to find a way to travel great distances faster than the speed of light (such as through wormholes), they would only just be aware of our existence if they were approximately 125 light-years away (the distance of how far Marconi’s first radio transmission has now travelled).

Recent studies from scientific journals have suggested that there may be a substantial number of sun-like stars that contain earth-like planets. In fact, according to the National Aeronautics and Space Administration (NASA), there are around 4,000 confirmed exoplanets, and over 3,000 of these are believed to be roughly the same size as Earth. Furthermore, the European Southern Observatory has determined that one in five sun-like stars have an earth-like planet in their habitable zone. Additionally, the Kepler Space Telescope has also discovered over 50 planets that have similar size, temperature, and composition to Earth. Taken together, these studies reveal that there are a substantial number of sun-like stars with earth-like planets that have been found.

I believe that the question that underlies Fermi’s Paradox, “where are all the aliens?” – and its relationship to the Drake equation, given the abundance of carbon and the number of exoplanets – may be answered in the very endeavors that he pursued. Given that the signature of nuclear weapons can be detected from space, would it come as no surprise to us, then, that any intelligent visitors from other planets would want to stealth themselves from our observation? When humanity has spent the better part of its modern era perfecting weapons of mass destruction, how is it that we can reasonably expect extragalactic civilizations to want to take calls or make talks with us, when we have no framework to enact a global, peaceful co-existence? Even NATO is defined as an alliance that depends upon the stockpile of nuclear weapons as a deterrent against warfare. As of yet, with the situation evolving in Ukraine, so, too, our nuclear weapons capabilities continue to evolve, becoming ever more precise with each turn of events.

So long as nuclear weapons and other means of mutually assured destruction are the primary means of domination, I doubt that we have any chance of hearing from intelligent life in the universe.

The official stance on UFOs/UAPs notwithstanding, another interesting and perhaps even more likely proposal:

Asymptotic burnout and homeostatic awakening: a possible solution to the Fermi paradox? by Michael L. Wong and Stuart Bartlett. May 4, 2022.

“Here, we place the emergence of cities and planetary civilizations in the context of major evolutionary transitions. With this perspective, we hypothesize that once a planetary civilization transitions into a state that can be described as one virtually connected global city, it will face an ‘asymptotic burnout’, an ultimate crisis where the singularity-interval time scale becomes smaller than the time scale of innovation. If a civilization develops the capability to understand its own trajectory, it will have a window of time to affect a fundamental change to prioritize long-term homeostasis and well-being over unyielding growth—a consciously induced trajectory change or ‘homeostatic awakening’. We propose a new resolution to the Fermi paradox: civilizations either collapse from burnout or redirect themselves to prioritizing homeostasis, a state where cosmic expansion is no longer a goal, making them difficult to detect remotely.”

If we take this proposal and other limitations such as communications into account, it is possible to explain why we have yet to detect evidence of intelligent extraterrestrial life. If a civilization is able to successfully redirect itself to prioritize long-term homeostasis, then it may be the case that they are out there, but just not detectable. Furthermore, it is also possible that civilizations are not able to make this shift in time, and instead succumb to the “asymptotic burnout”. Either way, the Fermi Paradox and the Drake Equation offer a valuable framework for understanding the possibility of humanity collectively meeting intelligent extraterrestrial life.

RELATED POST: War of the Worlds and the Invasion of the American Psyche


SETI Institute. Drake Equation. Retrieved from

Cramer, J. G. The Rare Earth Hypothesis. Retrieved from

Gray, R. H. (2018, August 2). The Fermi Paradox Is Not Fermi’s, and It Is Not a Paradox. Scientific American. Retrieved from

National Aeronautics and Space Administration (NASA). Retrieved from

European Southern Observatory. Retrieved from

Kepler Space Telescope. Retrieved from

Johansen, A., & Lam, F. (2022). Asymptotic burnout and homeostatic awakening: a possible solution to the Fermi paradox? Royal Society Open Science, 9(4), 20220029.

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