The Mediocrity Principle A Guiding Light in the Search for Extra-terrestrial Life

This month, I turn my attention outwards once again. The vastness of the cosmos has always captivated humanity's imagination, leading us to wonder if we are alone in the universe. The search for extra-terrestrial life has been a topic of fascination for scientists and enthusiasts alike. Amidst the countless stars and galaxies, the mediocrity principle has emerged as a fundamental concept guiding our exploration of potential cosmic neighbours. This principle posits that we should assume our circumstances and characteristics are typical rather than exceptional. 

For example, we now know that there are billions of galaxies in the universe, and each galaxy contains billions of stars. This means that there are an enormous number of planets in the universe, and many of these planets are likely to be similar to Earth in terms of their size, composition, and climate. As we apply the mediocrity principle to the quest for extra-terrestrial life, we find intriguing insights into the nature of our universe and our place within it.

Defining the Mediocrity Principle

The mediocrity principle, also known as the Copernican principle, stems from the realization that we do not occupy a privileged position in the cosmos. Developed initially by the ancient Greeks and later refined by Copernicus, it challenges our human-centric view of the universe. Rather than placing Earth and humanity at the centre of everything, the mediocrity principle suggests that we are merely one of many possible outcomes in a vast and diverse cosmos. The mediocrity principle suggests that if life can exist on Earth, it is likely to exist on other planets that are similar to Earth. 

This is because the conditions that are necessary for life on Earth are not unique. For example, the Earth's atmosphere contains the same gases that are found in other solar systems, and the Earth's oceans contain the same elements that are found in other stars

Applying the Principle to the Search for Extra-terrestrial Life

The mediocrity principle has important implications for the search for extra-terrestrial life. If the principle is correct, then it is likely that there is life on other planets in the universe. This means that our search for extra-terrestrial life should not be limited to Earth-like planets. Instead, we should be looking for planets that have the potential to support life, regardless of their physical characteristics. When it comes to the search for extra-terrestrial life, the mediocrity principle plays a pivotal role in shaping our expectations and guiding our methods. Instead of assuming that life on Earth is a rare exception, we should embrace the idea that life is likely to be a common occurrence in the universe. This assumption is based on several factors.

1.         Abundance of Habitability Zones: The mediocrity principle recognizes that Earth is not unique in its ability to support life. The discovery of exoplanets within the habitable zones of their stars suggests that conditions suitable for life are widespread throughout the cosmos. As we find more potentially habitable worlds, the likelihood of extra-terrestrial life increases.

2.         Life's Resilience: Life on Earth has demonstrated its resilience, thriving in diverse environments, from the freezing Arctic to the scorching depths of hydrothermal vents. The mediocrity principle suggests that life is not restricted to perfect conditions, making it more likely to exist in various forms across the universe.

3.         The Prevalence of Organic Molecules: The abundance of organic molecules discovered in interstellar space and on celestial bodies indicates that the building blocks of life are widespread. This further supports the idea that life could be a common phenomenon throughout the universe.

4.         The Immensity of Cosmic Time and Space: The universe is nearly 14 billion years old, and it contains more than two trillion galaxies. The sheer vastness of space and time increases the likelihood of multiple opportunities for life to emerge and evolve, especially given the billions of potentially habitable planets out there.

The Fermi Paradox

The mediocrity principle is often contrasted with the Fermi paradox, which is a paradox that asks why we have not yet encountered extra-terrestrial life. The Fermi paradox is named after Enrico Fermi, an Italian-American physicist who posed the paradox in the 1950s. Fermi argued that if the universe is teeming with life, then we should have already encountered some evidence of it. For example, we should have seen radio signals from other civilizations, or we should have found evidence of their presence on other planets. However, we have not seen any of these things, which leads to the paradox.

There are a number of possible explanations for the Fermi paradox. One possibility is that extra-terrestrial life is rare. Another possibility is that extra-terrestrial civilizations are not interested in contacting us. It is also possible that we have not been looking for extra-terrestrial life in the right places.

The mediocrity principle suggests that the Fermi paradox is not as puzzling as it seems. If the mediocrity principle is correct, then it is likely that there is life on other planets, but it is also likely that this life is not as advanced as our own. This means that extra-terrestrial civilizations may not have the technology to contact us, or they may not be interested in doing so

Implications for the Fermi Paradox

The mediocrity principle offers an interesting perspective on the Fermi Paradox, which ponders the apparent contradiction between the high probability of extra-terrestrial life and the lack of contact or evidence thereof. Enrico Fermi famously asked, "Where is everybody?"

The mediocrity principle suggests that the absence of contact is not evidence of the absence of extra-terrestrial life. Instead, it offers plausible explanations for the paradox. First, the vast distances between stars and galaxies might make interstellar travel exceedingly difficult, leading to limited contact opportunities. Second, advanced civilizations could be using communication methods beyond our current comprehension, making it challenging for us to detect their presence. Third, there might be cosmic barriers that prevent the spread of intelligent life across the galaxy.

Optimizing Our Search

The search for extra-terrestrial life is a complex and challenging endeavour. However, the mediocrity principle provides us with some hope that our search will be successful. If the principle is correct, then it is likely that there is life on other planets, and it is only a matter of time before we find it.

There are a number of different ways to search for extra-terrestrial life. One way is to look for radio signals from other civilizations. Another way is to look for planets that are similar to Earth in terms of their size, composition, and climate. We can also look for evidence of life on other planets, such as organic molecules or fossilized remains.

Embracing the mediocrity principle enhances our search strategies for extra-terrestrial life. Rather than focusing solely on Earth-like planets, we should consider a wider range of environments, as life might adapt to various conditions. Mars, for instance, once had liquid water and might still harbour life beneath its surface.

Furthermore, the search should not be limited to radio signals alone. Advanced civilizations might use other means of communication, such as lasers or advanced technologies we have not yet conceived.

The mediocrity principle also emphasizes the importance of collaboration and interdisciplinary approaches. The search for extra-terrestrial life is a grand scientific endeavour that requires the pooling of resources, knowledge, and ideas from astronomers, biologists, chemists, physicists, and more.

Conclusion

Of course, the mediocrity principle is not without its critics. Some scientists argue that the principle is based on too many assumptions, and that it is impossible to know for sure whether life is common in the universe. However, the mediocrity principle remains a powerful argument in favour of the existence of extra-terrestrial life, and it continues to guide the search for ET. As we explore the cosmos in search of extra-terrestrial life, the mediocrity principle serves as a guiding light, urging us to abandon anthropocentrism and embrace the vastness and diversity of the universe. By assuming that we are not unique, we open ourselves to a myriad of possibilities and increase our chances of making one of the most profound discoveries in human history. The search for extra-terrestrial life is an ongoing and exciting endeavour. The mediocrity principle gives us hope that our search will be successful, and it provides us with a framework for understanding the possibilities. As we continue to explore the universe, we may one day find the evidence we are looking for, and we may finally know whether we are alone in the universe. Whether we eventually find cosmic companions or not, the journey itself expands our understanding of the cosmos and our place within it, reinforcing the wonder and beauty of our ongoing exploration.

What it will mean to find Earth's Twin out there

One of the most ancient and perhaps the most enduring questions that humankind has been asking since picking up the first stone and striking fire has been around the topic of who we are and what are we doing here. Is there a destiny or are we just result of random mutations through a cycle which started billions of years ago.

Related to search for our place in the universe are the questions relating to whether there are worlds out there which are earth like. At first the whole question of whether there are any extra solar planets at all was a huge problem for us. It was indeed a formidable question for our kind with our primitive equipment and the ability to squint through the fog of earth’s atmosphere and then the gaseous envelop of our solar system. Through this foggy and often obscured picture, we used to wonder if there are any other rocks circling other stars. Logic of course told us that formation of the solar system shouldn’t be unique process which happened only in our neighborhood, but our ability to experimentally and by observation prove what was common sense was limited.

Well, not any more. For quite some time, we have been able to at least deduce the existence of extra solar planets, if not see them directly. An exoplanet (or extra solar planet) is a planet orbiting a star different from the Sun (the "exo" prefix means "outside" in Greek). Up until now, one has found mainly gas giant planets, which are easier to detect than telluric planets. An exoplanet or extra solar planet is a planet that does not orbit the Sun and instead orbits a different star, stellar remnant, or brown dwarf. More than 1800 exoplanets have been discovered (1849 planets in 1160 planetary systems including 471 multiple planetary systems as of 2 November 2014).

According to Observatoire de Paris - The planets of the solar system can be divided into two groups, the telluric planets and the gas giant (or "Jovian") planets. The telluric planets are spherical bodies with a crust of rock, and the gas giant planets are spheres composed of gas and ice (Jupiter, Saturn, Uranus and Neptune). Pluto is a solid body, whose composition consists of a variety of rocks and ices. An exoplanet (or extra solar planet) is a planet orbiting a star different from the Sun (the "exo" prefix means "outside" in Greek). Up until now, one has found mainly gas giant planets, which are easier to detect than telluric planets. However, due to the increasing sensitivity of the detection methods, one already begins to observe the first planets of sizes comparable to the Earth.

So, as we can see, thousands have been discovered in the past two decades, mostly with NASA's Kepler space telescope. The first extra solar planet discovery was confirmed in 1992, although they had been predicted long before. Planets are difficult to detect directly because they are so much dimmer than the stars they orbit. The Sun is a billion (10⁹) times brighter than Jupiter and 10 billion (10¹⁰) times brighter than the Earth.

According to space.com - These worlds come in a huge variety of sizes and orbits. Some are gigantic planets hugging close to their parent stars; others are icy, some rocky. NASA and other agencies are looking for a special kind of planet: one that’s the same size as Earth, orbiting a sun-like star in the habitable zone. The habitable zone is the range of distances from a star where a planet’s temperature allows liquid water oceans, critical for life on Earth. The earliest definition of the zone was based on simple thermal equilibrium, but current calculations of the habitable zone include many other factors, including the greenhouse effect of a planet’s atmosphere. This makes the boundaries of a habitable zone "fuzzy."

There are various available methods for detection of these extra solar planets, short of visiting them with FTL ships. If one is interested in details of various methods, then please visit website of Las Cumbres Observatory.

But a more interesting question is – what would be the social impact of a finding of Earth’s Twin out there? There is a lot of interest in the study of this phenomenon across the world by both religious and political leaders – for the same obvious reasons. Most of the apprehensions border on possibility of chaos and widespread anarchy. Why? Well you have to take a deep look at how our society has been structured since the birth of formal civilization thousands of years ago.

According to Wikipedia - The cultural impact of extraterrestrial contact is the corpus of changes to terrestrial science, technology, religion, politics, and ecosystems resulting from contact with an extraterrestrial civilization. Although closely related to it, the study of the cultural impact of extraterrestrial contact is distinct from the search for extraterrestrial intelligence (SETI), which attempts to locate intelligent life as opposed to analyzing the implications of contact with that life. The potential changes from extraterrestrial contact could vary greatly in magnitude and type, based on the extraterrestrial civilization's level of technological advancement, degree of benevolence or malevolence, and level of mutual comprehension between itself and humanity. The medium, through which humanity is contacted, be it electromagnetic radiation, direct physical interaction, extraterrestrial artifact, or otherwise, may also influence the results of contact. Incorporating these factors, various systems have been created to assess the implications of extraterrestrial contact. The implications of extraterrestrial contact, particularly with a technologically superior civilization, have often been likened to the meeting of two vastly different human cultures on Earth, an historical precedent being the Columbian Exchange. Such meetings have generally led to the destruction of the civilization receiving contact (as opposed to the "contactor", which initiates contact), and therefore destruction of human civilization is a possible outcome. However, the absence of any such contact to date means such conjecture is largely speculative.

According to an article on The Conversation - Habitable exoplanets are bad news for humanity. What did not make the news, however, is that this discovery also slightly increases how much credence we give to the possibility of near-term human extinction. This is because of a concept known as the Great Filter. The author hopes for a barren Kepler-186f and argues - If Kepler-186f is teeming with intelligent life, then that would be really bad news for humanity.

As philosopher Nick Bostrom once said: - The silence of the night sky is golden … in the search for extraterrestrial life, no news is good news. It promises a potentially great future for humanity.

In my opinion, this is a way different way of approaching a monumental question of whether we are alone in the universe, or ever have been? Doomsday scenarios abound across the literature of our species. But I ask why should it always be an extinction trajectory?

Well, as it turns out – according to space.com - Announced on July 23, 2015, planet Kepler-452b is larger than Earth and orbits a star nearly identical to the sun, but older and therefore hotter. The planet's orbit is nearly the same as Earth's, and its year is about 20 days longer than Earth's. Kepler-452b is 1,400 light-years away.

John Traveler in this article - What the Discovery of Earth Sized Exoplanets Means for the Human Race – goes on to say - To find that we are not alone in the vast cosmos will undoubtedly have substantial impact on human cultural, socio-religious, and intellectual paradigms. It’s safe to predict, such a discovery might have the greatest impact on human perspectives since ancient humans first experienced the cognitive foundations of logical thought and reason.

I firmly believe that human society would be changed for the better. Of course there will be some changes which a certain section of society might not like. The strangle hold that our current political and religious organizations have upon us would be loosened a bit. We may even suffer through a period when the faith system collapses, forcing humanity to start believing in itself rather than a divine intervention and overseeing. But we will pull through. We have come a long way in the last 400 years and we have survived 200,000 years of super volcanoes, earthquakes, global climate changes, flooding of epic proportions, genetic changes, and epidemics and have achieved, well almost, a global civilization.

My hopes for humanity are high. More on this in the next post.