III. An Organic Habitable Zone UniVerse
G. Anthropic, Biotropic, Earthropic Principles
Barrow, John, et al, eds. Fitness of the Cosmos for Life: Biochemistry and Fine-Tuning. Cambridge: Cambridge University Press, 2007.
Anthropic Principle. www.anthropic-principle.com. This website managed by philosopher Nick Bostrom is a good source of almost everything about this subject and comes with a primer and extensive bibliography.
Here you will find both popular overviews and scholarly material on everything related to observation selection effects, the anthropic principle, self-locating belief, and associated applications and paradoxes in science and philosophy.
Consolidation of Fine-Tuning. http://finetune.physics.ox.ac.uk/. This is a Templeton funded website, online mid 2015, with an original astrophysicist core of Roger Davies, David Sloan, Khalil Chamcham, Rafael Batista and Joseph Silk. Click an Events tab for workshops such as Life in the Universe, Other Earths, and Stars, Galaxies, and the Multiverse. Programs can be viewed, and for the first meeting, abstracts and slides by speakers Ard Louis, Bernard Carr, and George Ellis, for example second quote. A book is planned in 2018 with the website title from presentations from at a Physics of Fine Tuning Conference held in June 2017, (https://icpfit.physics.ox.ac.uk/). Speakers included Fred Adams, Luke Barnes, Joe Silk, an array whom are wondering about very curious energetic and atomic qualities. Some chapters have been posted, search A. Loeb, M. Livio.
Our goal is to consolidate the idea of fine-tuning across disciplines such as biology, chemistry, and physics. Fine-tuning is often deemed a fact and used to reach grandiose metaphysical conclusions by philosophers, theologians, and even physicists, without a proper understanding of the underlying assumptions entailed by these arguments. We intend to present a comprehensive review of the physics used for deriving fine-tuning arguments, scrutinising the current ones and uncovering new examples, thereby providing a solid foundation for future efforts to interpret this fascinating facet of Nature. (Mission)
Adams, Fred and Evan Grohs. Stellar Helium Burning in Other Universes: A Solution to the Triple Alpha Fine-Tuning Problem. arXiv:1608.04690. In these days of multiverse studies, a University of Michigan physicist and an astronomer enlist a new parameter by which a relative cosmic habitability might be quantified. As the Abstract notes this involves a nuance upon relative propensities to make carbon atoms vital for life and evolution. And might we then wonder for what reason can sapient creatures on a tiny ovular world be able to lately survey and quantify such infinite vistas?
Motivated by the possible existence of other universes, with different values for the fundamental constants, this paper considers stellar models in universes where 8Be is stable. Many previous authors have noted that stars in our universe would have difficulty producing carbon and other heavy elements in the absence of the well-known 12C resonance at 7.6 MeV. This resonance is necessary because 8Be is unstable in our universe, so that carbon must be produced via the triple alpha reaction to achieve the requisite abundance. This paper focuses on stellar models that burn helium into beryllium; once the universe in question has a supply of stable beryllium, carbon production can take place during subsequent evolution in the same star or in later stellar generations. Using both a semi-analytic stellar structure model as well as a state-of-the-art stellar evolution code, we find that viable stellar configurations that produce beryllium exist over a wide range of parameter space. Finally, we demonstrate that carbon can be produced during later evolutionary stages. (Abstract excerpts)
Balbus, Steven. Dynamical, Biological, and Anthropic Consequences of Equal Lunar and Solar Angular Radii. Proceedings of the Royal Society A. Online June, 2014. An Oxford University astrophysicist muses that similar included angles for sun light and moon beams, although located far apart, have provided long stable periods of tidal pools for life to complexify, form limbs and to come aground. OK
The nearly equal lunar and solar angular sizes as subtended at the Earth is generally regarded as a coincidence. This is, however, an incidental consequence of the tidal forces from these bodies being comparable. Comparable magnitudes implies strong temporal modulation, as the forcing frequencies are nearly but not precisely equal. We suggest that on the basis of paleogeographic reconstructions, in the Devonian period, when the first tetrapods appeared on land, a large tidal range would accompany these modulated tides. This would have been conducive to the formation of a network of isolated tidal pools, lending support to A.S. Romer's (1933) classic idea that the evaporation of shallow pools was an evolutionary impetus for the development of chiridian limbs in aquatic tetrapodomorphs. Since even a modest difference in the Moon's angular size relative to the Sun's would lead to a qualitatively different tidal modulation, the fact that we live on a planet with a Sun and Moon of close apparent size is not entirely coincidental: it may have an anthropic basis. (Abstract)
Ball, Philip and Eshel Ben-Jacob. Water as the Fabric of Life. European Physical Journal Special Topics. Online February, 2014. The British science writer and a Tel Aviv University biophysicist introduce an issue on novel appreciations of this vital fluid sustenance. By several unique features such as “strong solvent-induced forces for protein-folding,” water is seen to possess an array of properties analogous to physical phenomena, which then seem uncannily suitable for biology and evolution. Altogether an ordained, organic nature is ever implied, as if a fertile, amniotic, embryonic cosmos.
Many share the feeling that we are at in the midst of a shift in our perception of water – a shift from the current molecular-level based approach (which focuses on the behaviour of individual or small numbers of molecules) towards a new, systemic view of water. In this new picture, water is perceived as an active substance that responds adaptively to external and internal constraints and signals. These responses can have profound effects on substances immersed in water, and in particular on the functioning of biological constituents, from molecules to living cells. This special volume presents some existing and possible future directions in this trend towards a systemic view of water as an active substance, which plays many essential roles in sustaining life. The work reported here suggests that the notion of water as “life's solvent” should give way to the new realisation of water as an active “fabric of life”, continuously engaging and interacting with biomolecules in complex and subtle ways. (Abstract)
Barnes, Luke. Testing the Multiverse: Bayes, Fine-Tuning and Typicality. arXiv:1704.01680. The University of Sydney astronomer (search) posts his presentation at a 2014 London Philosophy of Cosmology conference, whose proceedings are to appear in June 2017, search Khalil Chamcham. As a coauthor with Geraint Lewis of A Fortunate Universe (2016), this entry discusses anthropic themes along with Bayesian “theory testing” methods for better iterations of “relative certainties or credences.” It is scary wondrous that inquisitive, globally cognizant peoples can imagine whole cosmoses at all. With 400th anniversary events underway for Galileo, what can these expansive vistas from our moon to a multiverse ever portend? As latest currents seem to presage, human beings ought to have a significant purpose in the actual scheme of things. See also a later edition Fine-Tuning in the Context of Bayesian Theory Testing at arXiv:1707.03965.
Theory testing in the physical sciences has been revolutionized in recent decades by Bayesian approaches to probability theory. Here, I will consider Bayesian approaches to theory extensions, that is, theories like inflation which aim to provide a deeper explanation for some aspect of our models (in this case, the standard model of cosmology) that seem unnatural or fine-tuned. In particular, I will consider how cosmologists can test the multiverse using observations of this universe. (Abstract)
Barnes, Luke. The Fine-Tuning of the Universe for Intelligent Life. Publications of the Astronomical Society of Australia. 29/4, 2012. A University of Sydney astrophysicist, formerly at ETH Zurich, achieves one of the best 21st century entries on this issue since the 1986 tome The Anthropic Cosmological Principle. In so doing, it faces the problems that beset physical cosmology due to a tangle of string theories, multiverse versions, personal opinions, and so on. As a talking point, the paper reviews and sets aside Victor Stegner’s 2011 The Fallacy of Fine-Tuning: Why the Universe is Not Designed for Us, much afflicted by his atheism. In response, the evolutionary appearance of reflective sentience able to gain such witness is indeed made possible by a unique concatenation of parameters, constants, and natural laws. Luke Barnes is careful in his measure, but the case is stated – at some point it need be asked and answered whether there is a greater reality made and meant for our edifying cognizance, or not.
The fine-tuning of the universe for intelligent life has received a great deal of attention in recent years, both in the philosophical and scientific literature. The claim is that in the space of possible physical laws, parameters and initial conditions, the set that permits the evolution of intelligent life is very small. I present here a review of the scientific literature, outlining cases of fine-tuning in the classic works of Carter, Carr and Rees, and Barrow and Tipler, as well as more recent work. We will touch on such issues as the logical necessity of the laws of nature; objectivity, invariance and symmetry; theoretical physics and possible universes; entropy in cosmology; cosmic inflation and initial conditions; galaxy formation; the cosmological constant; stars and their formation; the properties of elementary particles and their effect on chemistry and the macroscopic world; the origin of mass; grand unified theories; and the dimensionality of space and time. I also provide an assessment of the multiverse, noting the significant challenges that it must face. (Abstract excerpts)
Barrow, John. Life, the Universe, but Not Quite Everything. Physics World. 12/12, 1999. A millennium update on the perception of finely tuned physical constants that are indispensible for biological complexity.
….it is clear that there are many aspects of our universe’s global and local structure, and of its laws and other defining constants, that appear to be crucial for the existence of life as we know it. (34)
Barrow, John and Frank Tipler. The Anthropic Cosmological Principle. New York: Oxford University Press, 1986. Still a premier authoritative compendium both on this topic and a teleological universe. The presence of uniquely appropriate numerical qualities for the occurrence and evolution of life are noted from quantum domains to biochemical intricacies and onto astrophysical reaches.
Barrow, John, et al, eds. Fitness of the Cosmos for Life: Biochemistry and Fine-Tuning. Cambridge: Cambridge University Press, 2007. Reviewed more in An Organic Cosmos, in the tradition of Lawrence Henderson’s classic The Fitness of the Environment, these proceedings of a Templeton conference go beyond critical physical parameters suitable for our anthropic presence and show that myriad properties of biochemical and cellular materiality also seem precisely, uncannily tailored for the appearance and evolution of living entities. By this ‘biotropic’ addition, cosmic nature is further imbued with a fertile propensity for life and persons.
Bostrom, Nick. Anthropic Bias: Observation Selection Effects in Science and Philosophy. New York: Routledge, 2002. An extended thought experiment applied to anthropic reasoning which argues from various positions that human beings are here because of precise cosmic parameters. A wide ranging and clever essay which asks how much is this view affected by and dependent upon our biased persuasions.
Buchanan, Mark. Anthropic Attitudes. Nature Physics. 11/7, 2015. A commentary on The Fine-Tuning Argument by the Radford University mathematician Klaas Landsman, posted at arXiv:1505.05359, which sees five options: Designed, Multiverse, Blind chance, Pure necessity, or Misunderstood. But these are each summarily dismissed, so as to finish with Our Universe has not been fine-tuned for life: life has been fine-tuned to our Universe. This preconclusion has been challenged by later responses such as The Exoplanets Analogy to the Multiverse by the University of Sao Paulo physicist Osame Kinouchi at arXiv:1506.08060, whose Abstract is after Landsman.
Our laws of nature and our cosmos appear to be delicately fine-tuned for life to emerge, in a way that seems hard to attribute to chance. In view of this, some have taken the opportunity to revive the scholastic Argument from Design, whereas others have felt the need to explain this apparent fine-tuning of the clockwork of the Universe by proposing the existence of a `Multiverse'. We analyze this issue from a sober perspective. Having reviewed the literature and having added several observations of our own, we conclude that cosmic fine-tuning supports neither Design nor a Multiverse, since both of these fail at an explanatory level as well as in a more quantitative context of Bayesian confirmation theory (although there might be other reasons to believe in these ideas, to be found in religion and in inflation and/or string theory, respectively). In fact, fine-tuning and Design even seem to be at odds with each other, whereas the inference from fine-tuning to a Multiverse only works if the latter is underwritten by an additional metaphysical hypothesis we consider unwarranted. Instead, we suggest that fine-tuning requires no special explanation at all, since it is not the Universe that is fine-tuned for life, but life that has been fine-tuned to the Universe. (Landsman Abstract)