Is abiogenesis virtually impossible?

Question

Dr Eugene Koonin published a paper in 2007, The cosmological model of eternal inflation and the transition from chance to biological evolution in the history of life in the journal Biology Direct.

An appendix to the paper, titled Probabilities of the emergence, by chance, of different versions of the breakthrough system in an O-region: a toy calculation of the upper bounds claims:

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 ["observable region of the universe"] 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:

• two rRNAs with a total size of at least 1000 nucleotides

• ~10 primitive adaptors of ~30 nucleotides each, in total, ~300 nucleotides

• at least one RNA encoding a replicase, ~500 nucleotides (low bound)is required. In the above notation, 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.*

Koonin goes on to claim that this low probability is evidence that there is a multiverse with an infinite (or at least a hugely vast) amount of O-regions.

Is the probability of abiogenesis so small? Is this valid evidence to support a multiverse?

Answer 1

No, the article doesn't claim that probability of abiogenesis cannot be higher than 10^-1018.

The only claim it makes it that even if the probability of an event is as low as 10^-1018, it still can happen in a multiverse.

Dr Koonin mentions the more mainstream theories, which (if proven correct) may remove the need for an event of extremely low probability:

The commonly considered solution is the RNA world scenario, i.e., the notion that replication evolved before translation such that the earliest stage of life's evolution was a versatile community of replicating RNA molecules [21–23]. A central element of the RNA world is a replicase consisting of RNA. The RNA world concept is supported by the experimental discovery of diverse catalytic activities of ribozymes (catalytic RNAs) [24–27]. However, all the advances of ribozymology notwithstanding, the prospects of a bona fide ribozyme replicase remain dim as the ribozymes designed for that purposes are capable, at best, of the addition of ~10 nucleotides to a oligonucleotide primer, at a very slow rate and with fidelity at least an order magnitude below that required for the replication of relatively long RNA molecules [28, 29]. As recently noticed by one of the leading RNA world explorers, "Despite valiant efforts,...it appears unlikely that this particular polymerase enzyme will ever be evolved to the point that it can copy RNA molecules as long as itself (~200 nucleotides)" [30]. Of course, it remains possible – and this is, indeed, the belief in the RNA world community – that other ribozymes are eventually evolved to that level; however, the evidence is lacking.

All this is not to suggest that OORT is a problem of "irreducible complexity" and that the systems of replication and translation could not emerge by means of biological evolution. It remains possible that a compelling evolutionary scenario is eventually developed and, perhaps, validated experimentally.

Answer 2

This is not a scientific theory, because when it was published in 2007, there were no testable assumptions associated with multiverse theories (citation). Therefore it relies entirely on non-observable assumptions. In the most generic sense, our observable universe may be part of something finite or infinite in size, and either part of a multiverse or not. Because all scientific observation by definition takes place in the observable universe, we will never know which of the four possibilities is correct.

[aside: This does not rule out the possibility that in the future, a multiverse theory will arise which will provide a compelling explanation for observations and therefore become widely adapted by physicists. As of 2023 this is not yet the case. (citation)]

Claiming that abiogenesis has a probability of P < 10^-1018 and therefore proves something about the size of the universe is simply an argument from incredulity -- "I can't imagine something happening with a probability of P < 10^-1018 in a finite universe, so we must be in a multiverse" -- and works equally well as an argument for the existence of God. In reality, in our observable universe, the probability of abiogenesis is 1.