VII. Pedia Sapiens: A Genesis Future on Earth and in the Heavens
C. An Earthropic Principle: Novel Evidence About a Special Planet
Chopra, Aditya and Charles Lineweaver. The Case for a Gaian Bottleneck: The Biology of Habitability. International Journal of Astrobiology. 16/1, 2016. If one pays attention to current findings in the scientific literature, as this website tries to report, in the past few years the cosmic nexus of our Earthly abode has attained a special statue. Planetary systems with well spaced circular orbits, all in the same plane, a rare location of outer gas giants, a stable, long duration galaxy, and a large moon, are now known as quite rare. This paper by Australian Natural University astrophysicists now adds a temporal evolutionary constraint. While biochemical, microbial life appears wherever possible, an ability to reach complex, multicellular stages is seen to require an early formation of a conducive, self-regulating atmosphere. If this does not happen, simpler life forms are extinguished by hostile conditions, the candidate bioworld becomes barren. Even if the emergence of life is a common feature of wet rocky planets throughout the Universe, the Gaian bottleneck model suggests that inhabited Earth-like planets would be rare.
The prerequisites and ingredients for life seem to be abundantly available in the Universe. However, the Universe does not seem to be teeming with life. The most common explanation for this is a low probability for the emergence of life (an emergence bottleneck), notionally due to the intricacies of the molecular recipe. Here, we present an alternative Gaian bottleneck explanation: If life emerges on a planet, it only rarely evolves quickly enough to regulate greenhouse gases and albedo, thereby maintaining surface temperatures compatible with liquid water and habitability. Such a Gaian bottleneck suggests that (i) extinction is the cosmic default for most life that has ever emerged on the surfaces of wet rocky planets in the Universe and (ii) rocky planets need to be inhabited to remain habitable. In the Gaian bottleneck model, the maintenance of planetary habitability is a property more associated with an unusually rapid evolution of biological regulation of surface volatiles than with the luminosity and distance to the host star. (Abstract)
Chu, Ted. Human Purpose and Transhuman Potential: A Cosmic Vision for Our Future Evolution. San Rafael, CA: Origins Press, 2014. An international economist with degrees from Fudan University, Shanghai and a doctorate from Georgetown University, now based in Dubai, achieves a unique synthesis of traditional wisdom with our latest scientific transfigurative prowess. With a Foreword by theologian John Haught, it is made clear that he does not intend a machine takeover as the near Singularity. An early chapter records an original Axial Age for both Eastern and Western cultures, especially as a “Yin-Yang reality.” By these lights a Second Axial Age is proposed to commence an intentional transformative procreation of a Cosmic Being. The overall message, akin to the prescience of a Nikolai Fedorov and Pierre Teilhard, is an “hourglass view” (127) whence temporal creation does not end with us, but needs to wholly pass through its human phenomenon on earth, which has “a critical role in cosmic evolution.”
Cirkovic, Milan. Earths: Rare in Time, not Space? Journal of the British Interplanetary Society. 57/1-2, 2004. In attempt to move beyond the Rare Earth hypothesis, the Belgrade astronomer enlists a temporal factor whereby the Milky Way galaxy may be at the verge of a Phase Transition from a sparsely populated mode to being filled with centers of intentional intelligence. The present galactic moment is a “window of opportunity” when sentient observers may engage in their own “self-selection.”
The latter hypothesis (PT) suggests that our presence on Earth now selects a particular (and rather special) epoch of the history of the Milky Way: namely the epoch in which global regulation enables the emergence of complex, intelligent life forms. (57) However, our temporal location is rather special, since we are evolved complex metazoans on the verge – in terms of astrophysical timescales – of having capacities to leave our home biosphere and embark on the venture of Galactic colonization. (57)
Cirkovic, Milan. The Great Silence: Science and Philosophy of Fermi’s Paradox. Oxford: Oxford University Press, 2018. The Astronomical Observatory of Belgrade and Future of Humanity Institute, Oxford University astrophysicist and author (search) provides a thorough study of possible answers to Enrico Fermi’s famous query: with an infinity of suns and assumed worlds, the cosmos ought to be filled with signs of their presence, but they are nowhere to be seen. Thus follows an eclectic list of solipsist, rare-earth, neo-catastrophic, logistic, and so on guesses – they are hiding, we are toxic, it’s a zoo, too many natural or viral dangers, stick with your home base, arrested development, technological annihilation and more. A theme then courses through – while a “Copernican principle” need be held to such that Earth is not in any central location, a closing phrase is Many are called, but few are chosen. Since Earth life has made it through an evolutionary “Gaian Window,” maybe we are special after all (I may be reading this in) so that efforts to achieve sustainability ought to proceed. See also Where is Everybody? by Stephen Webb (2015), /The Future of Humanity by Michio Kaku (2018) and On the Future by Martin Rees (2018) for other takes. So some seven decades later, as an Earthropic Principle conveys, me + We = US could well be the It from Bit as participatory cosmic cocreators.
The Great Silence explores the multifaceted problem named after the great Italian physicist Enrico Fermi and his legendary 1950 lunchtime question "Where is everybody?" In many respects, Fermi's paradox is the richest and the most challenging problem for the entire field of astrobiology and the Search for ExtraTerrestrial Intelligence (SETI) studies. The book shows how Fermi's paradox is intricately connected with many fields of learning, technology, arts, and even everyday life. It aims to establish the strongest possible version of the problem, to dispel many related confusions, obfuscations, and prejudices, as well as to offer a novel point of entry to the many solutions proposed in existing literature. Milan Cirković argues that any evolutionary worldview cannot avoid resolving the Great Silence problem in one guise or another. (Publisher)
Cirkovic, Milan and Branislav Vukotic. Astrobiological Landscape: A Platform for the Neo-Copernican Synthesis? International Journal of Astrobiology. Online October, 2012. As the Abstract explains, Belgrade astronomers draw upon many findings that imply an abiding lively cosmos which inherently seeds itself with complexifying biomolecules, habitable zones, and myriad fertile exoearths. In regard, it is proposed to extend biology’s evolutionary or fitness landscape models to celestial reaches, a notable advance toward imagining a procreative genesis cosmos.
We live in the epoch of explosive development of astrobiology, a novel interdisciplinary field dealing with the origin, evolution and the future of life. The relationship between cosmology and astrobiology is much deeper than it is usually assumed – besides a similarity in the historical model of development of these two disciplines, there is an increasing number of crossover problems and thematic areas which stem from considerations of Copernicanism and observation selection effects. Such a crossover area is both visualized and heuristically strengthened by introduction of the astrobiological landscape, describing complexity of life in the most general context. We argue that this abstract landscape-like structure in the space of astrobiological parameters is a concept capable of unifying different strands of thought and research, a working concept and not only a metaphor. By analogy with phase spaces of complex physical systems, we can understand the astrobiological landscape as a set of viable evolutionary histories of life in a particular region of space. It is a notion complementary to the classical concept of biological morphological space, underscoring the fact that modern astrobiology offers a prospect of both foundational support and vast extension of the domain of applicability of the Darwinian biological evolution. Such a perspective would strengthen foundations upon which various numerical models can be built; the lack of such quantitative models has often been cited as the chief weakness of the entire astrobiological enterprise. (Abstract)
Dehant, Veronique, et al. Geoscience for Understanding Habitability in the Solar System and Beyond. Space Science Reviews. 215/42, 2019. Eighteen researchers from six European countries survey of how a wide range of variable internal and external geological and environmental conditions might affect a planet’s hospitality for evolutionary life. A tour is first taken of the Early Earth, Mars, Venus and outer worlds. How study of near and far exoplanets might progress is then scoped out. And as one reads along, it strikes how such a 21st century contribution as this need be attributed to an as yet unidentified worldwise, collective entity learning by her/his own self.
This paper reviews habitability conditions for a terrestrial planet from the point of view of geosciences. It addresses how interactions between the interior of a planet or a moon and its surface atmosphere, hydrosphere and biosphere might be able to sustain life. We address and debate questions issues such as: How do core and mantle affect the evolution and habitability of planets; Mantle overturn on the evolution of the interior and atmosphere; What is the role of the global carbon and water cycles; The influence of comet and asteroid impacts on the evolution of the planet; How does life interact with the evolution of the Earth’s geosphere and atmosphere; and How can knowledge of the solar system geophysics and habitability be applied to exoplanets. (Abstract excerpt, edit)
Emspak, Jesse. New Insights into How the Solar System Formed. Astronomy. May, 2018. As the quote says, a science writer explains how the latest results increasingly imply that our home incubator is a uniquely conducive milieu. While myriad stellar systems are usually beset with chaos, here our large, gaseous Jupiter appears to have uniquely coursed over billions of years inward and out to form the relatively benign, orderly array that Earth presently abides in.
2018. As the quote says, a science writer explains how the latest results increasingly imply that our home incubator is a uniquely conducive milieu. While myriad stellar systems are usually beset with chaos, here our large, gaseous Jupiter appears to have uniquely coursed over billions of years inward and out to form the relatively benign, orderly array that Earth presently abides in.
Foley, Bradford and Peter Driscoli. Whole Planet Coupling Between Climate, Mantle, and Core. arXiv: 1711.06801. Akin to solar systems being found to act in a coordinated manner, Carnegie Institute for Science geophysicists describe globally dynamic interactions between interior, surface and atmospheric phases, whence an integral bioworld acts as a unitary entity. As a result, another finely choreographed synchrony is required so as to achieve long-term evolutionary habitability.
Earth's climate, mantle, and core interact over geologic timescales. Climate influences whether plate tectonics can take place on a planet, with cool climates being favorable for plate tectonics because they enhance stresses in the lithosphere, suppress plate boundary annealing, and promote hydration and weakening of the lithosphere. Coupling between climate, mantle, and core can potentially explain the divergent evolution of Earth and Venus. As Venus lies too close to the sun for liquid water to exist, there is no long-term carbon cycle and thus an extremely hot climate. On planets within the habitable zone where liquid water is possible, a wide range of evolutionary scenarios can take place depending on initial atmospheric composition, bulk volatile content, or the timing of when plate tectonics initiates, among other factors. Many of these evolutionary trajectories would render the planet uninhabitable. (Abstract)
Forgan, Duncan. Spatio-Temporal Constraints on the Zoo Hypothesis. International Journal of Astrobiology. Online May, 2011. A Scottish Universities Physics Alliance astronomer finds flaws in the view that extraterrestrial intelligences or civilizations have not been detected because they do not want us to do so. But possibly a reason might be one might add, in a genesis universe akin to an egg whose embryo must be able to hatch itself as a measure of fitness, we earthkind need ultimately come to our collective, peaceable senses and decisively select ourselves as a successful, organically harmonious, center of future life and creation.
Forget, Francois. On the Probability of Habitable Planets. International Journal of Astrobiology. 12/3, 2013. With the rush of Kepler satellite discoveries of a Milky Way and universe filled with solar systems and orbital objects of every kind, the prevalence, or absence, of earth-analog bioworlds has become a prime issue. An Institute Pierre Simon Laplace, Universite Paris, astrophysicist here provides a succinct technical survey. Four classes of conducive worlds are cited: Planets like this with suitable water, atmosphere, and stabilities; Earth-like but unable to hold aqueous seas; Worlds with too much water and/or geothermal activity; and Ice covered, frozen globes. A suggestive allusion as made by Paul Davies, John Gribbin and others, is that in some real way our minute, self-regulating orb just flickering into knowing consciousness may be of immense significance after all.
In the past 15 years, astronomers have revealed that a significant fraction of the stars should harbor planets and that it is likely that terrestrial planets are abundant in our galaxy. Among these planets, how many are habitable, i.e. suitable for life and its evolution? Liquid water remains the key criterion for habitability. It can exist in the interior of a variety of planetary bodies, but it is usually assumed that liquid water at the surface interacting with rocks and light is necessary for the emergence of a life able to modify its environment and evolve. A first key issue is thus to understand the climatic conditions allowing surface liquid water assuming a suitable atmosphere. This have been studied with global mean 1D models which has defined the “classical habitable zone”, the range of orbital distances within which worlds can maintain liquid water on their surfaces. A new generation of 3D climate models based on universal equations and tested on bodies in the solar system is now available to explore with accuracy climate regimes that could locally allow liquid water. A second key issue is now to better understand the processes which control the composition and the evolution of the atmospheres of exoplanets, and in particular the geophysical feedbacks that seems to be necessary to maintain a continuously habitable climate. From that point of view, it is not impossible that the Earth’s case may be special and uncommon. (Abstract)
Light of the Stars: Alien Worlds and the Fate of the Earth.
New York: Norton,
The University of Rochester astrophysicist and author (search UR) provides a latest survey of the 2ist century revolutionary witness of an innately planet and solar system making cosmos, which begets living systems and a global sapience able to learn this. The unique work is an insider’s view of profligate biospheres and maybe noospheres, citing Vernadsky, Teilhard, Lovelock and Lynn Margulis, which infer a growing sense of an inherent astrobiology. But these findings lead us to realize that our Anthropocene moment is due to many rare, favorable twists and turns along the way.
From this perspective, civilizations become just another thing the Universe does, like solar flares or comets. We can use what the stars have laid out before us in our astrobiological studies to explore how any civilization on any planet can – or, in the worst case, cannot – evolve together. The advantages of this astrobiological perspective can be gained even if no other civilization ever existed. Thinking about hypothetical exo-civilizations is valuable in dealing with the challenge of the Anthropocene because it reaches us to “think like a planet.” It teaches us to frame our pathways to a long-term project of civilization in terms of the coevolution between life and the Earth. (15)
Frank, Adam and Woodruff Sullivan. A New Empirical Constraint on the Prevalence of Technological Species in the Universe. arXiv:1510.08837. The University of Rochester and University of Washington astronomers update the Drake equation (search Vakoch) by way of the latest rush of satellite exoplanet findings to boost chances that our prodigious planet is not alone. See also A Population-Based Habitable Zone Perspective by Andras Zsom at arXiv:1510.06885.
In this paper we address the cosmic frequency of technological species. Recent advances in exoplanet studies provide strong constraints on all astrophysical terms in the Drake Equation. Using these and modifying the form and intent of the Drake equation we show that we can set a firm lower bound on the probability that one or more additional technological species have evolved anywhere and at any time in the history of the observable Universe. We find that as long as the probability that a habitable zone planet develops a technological species is larger than ~10−24, then humanity is not the only time technological intelligence has evolved. This constraint has important scientific and philosophical consequences. (Abstract)