Eugene V. Koonin is a Senior Investigator at the National Center for Biotechnology Information, which is part of the National Library of Medicine, a branch of the National Institutes of Health, in Bethesda, Maryland, USA. He is a recognized expert in the field of evolutionary and computational biology. He is also the author of The Logic of Chance: The Nature and Origin of Biological Evolution (Upper Saddle River: FT Press, 2011, ISBN 978-0-13-262317-9). I think we can fairly assume that when it comes to origin-of-life scenarios, he knows what he’s talking about.
In Appendix B of his book, The Logic of Chance, Dr. Koonin argues that the origin of life is such a remarkable event that we need to postulate a multiverse, containing a very large (and perhaps infinite) number of universes, in order to explain the emergence of life on Earth. Dr. Koonin is an enthusiastic proponent of the eternal inflation model of the cosmos (which was proposed in 2007 by physicist Alan Guth). According to this model, all possible series of events (or in physics jargon, all macroscopic histories) which are allowed by the laws of physics are repeated an infinite number of times in the infinite multiverse. What we call “our universe” is simply the observable region (O-region) within a vast and infinite multiverse. Dr. Koonin is quite upfront about what this means. In his words:
There is, e.g., an infinite number of (macroscopically) exact copies of the earth with everything that exists on it, although the probability that a given observable region of the universe (hereinafter O-region) carries one of such copies is vanishingly tiny.
Dr. Koonin invokes a version of the anthropic principle in order to explain why the physical constants of our universe (or O-region) are compatible with the existence life. According to the anthropic principle, the only “reason” our universe has these constants is that if it didn’t, we wouldn’t be here!
However, Dr. Koonin contends that the physical constants and initial conditions of our universe are insufficient to explain the origin of life on Earth. Only if our universe is part of a larger multiverse, in which all possible scenarios are played out, does the emergence of life on Earth become likely.
The reason why Dr. Koonin believes we need to postulate a multiverse in order to solve the riddle of the origin of life on Earth is that all life is dependent on replication and translation systems. These systems are fiendishly complex. As Koonin puts it:
The origin of the translation system is, arguably, the central and the hardest problem in the study of the origin of life, and one of the hardest in all evolutionary biology. The problem has a clear catch-22 aspect: high translation fidelity hardly can be achieved without a complex, highly evolved set of RNAs and proteins but an elaborate protein machinery could not evolve without an accurate translation system.
Dr. Koonin claims that the emergence of even a basic replication-translation system on the primordial Earth is such an astronomically unlikely event that we would need to postulate a vast number of universes, in which all possible scenarios are played out, in order to make its emergence likely.
To justify this claim, Dr. Koonin provides what he calls “a rough, toy calculation of the upper bound of the probability of the emergence of a coupled replication-translation system in an O-region.” The calculations on pages 434-435 in Appendix B of Dr. Koonin’s book, The Logic of Chance, are adapted from his peer-reviewed article, The Cosmological Model of Eternal Inflation and the Transition from Chance to Biological Evolution in the History of Life, Biology Direct 2 (2007): 15, doi:10.1186/1745-6150-2-15. As readers can verify for themselves, the wording is virtually identical in the 2007 article. I shall reproduce the relevant passage below (bold emphases are mine – VJT):
Probabilities of the emergence, by chance, of different versions of the breakthrough system in an O-region: a back-of-the-envelope calculation of the upper bounds
General assumptions: an O-region contains 1022 stars and every 10th star has a habitable planet, hence 1021 habitable planets (undoubtedly, a gross over-estimation because, in reality, most stars have no planets at all, let alone habitable ones). Each planet is the size of earth and has a 10 kilometer (106 cm) thick habitable layer; hence the volume of the habitable layer is 4/3π[R3-(R-l)3] ≈ 5 × 1024 cm3, where R is the radius of the planet and l is the thickness of the habitable layer. RNA synthesis occurs in 1% of the volume of the habitable layer, i.e., a volume V ≈ 5 × 1022 cm3 is available for RNA synthesis (a gross over-estimation – in reality, there would be very few “RNA-making reactors”). Let the concentration of nucleotides in volume V and the rate of the synthesis of RNA molecules of size n (a free parameter depending on the specific model of the breakthrough stage; hereinafter n-mer) be 1 molecule/cm3/second (a gross overestimate for any sizable molecule; furthermore, the inverse dependence on n, which is expected to be strong, is disregarded). The time available after the Big Bang of the given O-region (as an upper bound) of all planets in it is 1010 years ≈ 3 × 1017 seconds. Then the number of unique n-mers “tried out” during the time after the Big Bang is this:
S ≈ 5 × 1022 × 1021 × 3 × 1017 ≈ 1.5 × 1061.
Let us assume that, for the onset of biological evolution, a unique n-mer is required. The number of such sequences is N = 4n ≈100.6n.
Then, the expectation of the number of times a unique n-mer emerges in an O-region is this:
E = S/N = 1.5 × 1061/100.6n and n = log(E × 1.5 × 1061)/0.6.
Substituting E = 1, we get n ≈102 (nucleotides). Note that, because n is proportional to logS, the estimate is highly robust to the assumptions on the values of the contributing variables; e.g., a order of magnitude change in S will result in an increase or decrease of n by less than 2 nucleotides.
A ribozyme replicase consisting of ~100 nucleotides is conceivable, so, in principle, spontaneous origin of such an entity in a finite universe consisting of a single O-region cannot be ruled out in this toy model (again, the rate of RNA synthesis considered here is a deliberate, gross over-estimate).
The requirements for the emergence of a primitive, coupled replication-translation system, which is considered a candidate for the breakthrough stage in this paper, are much greater. At a minimum, spontaneous formation of the following is required:
– Two rRNAs with a total size of at least 1000 nucleotides
– Approximately 10 primitive adaptors of about 30 nucleotides each, for a total of approximately 300 nucleotides
– At least one RNA encoding a replicase, about 500 nucleotides (low bound)is required. Under the notation used here, n = 1800, resulting in E <10-1018.
In other words, even in this toy model that assumes a deliberately inflated rate of RNA production, the probability that a coupled translation-replication emerges by chance in a single O-region is P < 10-1018. Obviously, this version of the breakthrough stage can be considered only in the context of a universe with an infinite (or, at the very least, extremely vast) number of O-regions.
The model considered here is not supposed to be realistic by any account. It only serves to illustrate the difference in the demands on chance for the origin of different versions of the breakthrough system and, hence, the connections between these versions and different cosmological models of the universe.
Dr. Koonin’s 2007 paper, which contained the above calculations, passed a panel of four reviewers, including one from Harvard University, who wrote:
In this work, Eugene Koonin estimates the probability of arriving at a system capable of undergoing Darwinian evolution and comes to a cosmologically small number. With such an improbable event at hand, Koonin turns to a cosmological perspective in order to grasp its feasibility. He cites recent work in cosmology that highlights the vastness of the universe, where any series of events is necessarily played out an infinite number of times. This so-called “many-worlds in one” model essentially reconceives any chance event as a necessary one, where its (absolute) abundance is proportional to its chance of occurring.
The context of this article is framed by the current lack of a complete and plausible scenario for the origin of life. Koonin specifically addresses the front-runner model, that of the RNA-world, where self-replicating RNA molecules precede a translation system. He notes that in addition to the difficulties involved in achieving such a system is the paradox of attaining a translation system through Darwinian selection. That this is indeed a bona-fide paradox is appreciated by the fact that, without a shortage [of] effort, a plausible scenario for translation evolution has not been proposed to date. There have been other models for the origin of life, including the ground-breaking Lipid-world model advanced by Segrè, Lancet and colleagues (reviewed in EMBO Reports (2000), 1(3), 217–222), but despite much ingenuity and effort, it is fair to say that all origin of life models suffer from astoundingly low probabilities of actually occurring…
Overall, this is a bold manuscript that promises to deeply influence the stream of thought on the origin of life…
…[F]uture work may show that starting from just a simple assembly of molecules, non-anthropic principles can account for each step along the rise to the threshold of Darwinian evolution. Based upon the new perspective afforded to us by Koonin this now appears unlikely. (Emphases mine – VJT.)
Is there any atheist out there who is foolhardy enough to argue with this Harvard scientist, and claim that there is an elementary flaw in Dr. Koonin’s calculations, which the Harvard scientist overlooked, and that Koonin’s argument is just a modern-day example of Hoyle’s fallacy? Go on, I dare you! Knock yourself out!
Does the multiverse solve the problem of the origin of life?
Dr. Koonin contends that in an infinite multiverse where all possible scenarios are played out, life is bound to emerge sooner or later. What Dr. Koonin overlooks, however, is that a multiverse would itself need to be highly fine-tuned, as Dr. Robin Collins has argued in an influential essay entitled, The Teleological Argument: An Exploration of the Fine-Tuning of the Universe (in The Blackwell Companion to Natural Theology, edited by William Lane Craig and J. P. Moreland, 2009, Blackwell Publishing Ltd.):
…[T]he fundamental physical laws underlying a multiverse generator – whether of the inflationary type or some other – must be just right in order for it to produce life-permitting universes, instead of merely dead universes…
In sum, even if an inflationary-superstring multiverse generator exists, it must have just the right combination of laws and fields for the production of life-permitting universes: if one of the components were missing or different, such as Einstein’s equation or the Pauli Exclusion Principle, it is unlikely that any life-permitting universes could be produced. Consequently, at most, this highly speculative scenario would explain the fine-tuning of the constants of physics, but at the cost of postulating additional fine-tuning of the laws of nature.
Dr. Robin Collins took his argument one step further several years ago, in a lecture he gave at Stanford University, entitled, Universe or Multiverse? A Theistic Perspective, where he argued (see section 6) that the multiverse hypothesis is unable to account for the beauty of the laws of nature:
…[W]e inhabit a world that could be characterized as a world of fundamental simplicity that gives rise to the enormous complexity needed for intelligent life…
For example, although the observable phenomena have an incredible variety and much seeming chaos, they can be organized via a relatively few simple laws governing postulated unobservable processes and entities. What is more amazing, however, is that these simple laws can in turn be organized under a few higher-level principles … and form part of a simple and elegant mathematical framework…
Further, this “fine-tuning” for simplicity and elegance cannot be explained either by the universe-generator multiverse hypothesis or the metaphysical multiverse hypothesis, since there is no reason to think that intelligent life could only arise in a universe with simple, elegant underlying physical principles. Certainly a somewhat orderly macroscopic world is necessary for intelligent life, but there is no reason to think this requires a simple and elegant underlying set of physical principles.
One way of putting the argument is in terms of the “surprise principle” we invoked in the argument for the fine-tuning of the constants of intelligent life. Specifically, as applied to this case, one could argue that the fact that the phenomena and laws of physics are fine-tuned for simplicity with variety is highly surprising under the non-design hypothesis, but not highly surprising under theism. Thus, the existence of such fine-tuned laws provides significant evidence for theism over the non-design hypothesis.
In other words, by appealing to the multiverse in order to explain the origin of life on Earth, Dr. Koonin has generated an even bigger problem: explaining the fine-tuning of the multiverse itself.
To cap it all, since Dr. Koonin’s book, The Logic of Chance was published, cosmologist Dr. Alex Vilenkin has acknowledged that current scientific evidence indicates that even if there is a multiverse, it too would have had a beginning (see here).
Nevertheless, I would like to take my hat off to Dr. Koonin for frankly recognizing the magnitude of the problem of life’s origin.
What do readers think?
Yuri I. Wolf and Eugene V. Koonin, On the origin of the translation system and the genetic code in the RNA world by means of natural selection, exaptation, and subfunctionalization, Biology Direct 2007; 2: 14, doi: 10.1186/1745-6150-2-14.
Eugene V. Koonin, The Cosmological Model of Eternal Inflation and the Transition from Chance to Biological Evolution in the History of Life, Biology Direct 2 (2007): 15, doi:10.1186/1745-6150-2-15.