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Claim: Complex self-replicating molecules can emerge spontaneously and relatively easily from simple chemical reaction systems

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Image result for origin of life NASA From Yu Liu and David Sumpter at ArXiv:

Spontaneous emergence of self-replication in chemical reaction systems

Explaining the origin of life requires us to explain how self-replication arises. To be specific, how can a self-replicating entity develop spontaneously from a chemical reaction system in which no reaction is self-replicating? Previously proposed mathematical models either supply an explicit framework for a minimal living system or only consider catalyzed reactions, and thus fail to provide a comprehensive theory. We set up a general model for chemical reaction systems that properly accounts for energetics, kinetics and the conservation law. We find that (1) some systems are collectively-catalytic where reactants are transformed into end products with the assistance of intermediates (as in the citric acid cycle), while some others are self-replicating where different parts replicate each other and the system self-replicates as a whole (as in the formose reaction); (2) many alternative chemical universes often contain one or more such systems; (3) it is possible to construct a self-replicating system where the entropy of some parts spontaneously decreases, in a manner similar to that discussed by Schrodinger; (4) complex self-replicating molecules can emerge spontaneously and relatively easily from simple chemical reaction systems through a sequence of transitions. Together these results start to explain the origins of prebiotic evolution. (abstract) pdf. More.

If life can “emerge spontaneously and relatively easily from simple chemical reaction systems through a sequence of transitions,” why don’t we ever see it happening today?

The Darwinsplaining usually amounts to the claim that a spontaneously assembling life form today would be eaten by more advanced organisms. But that’s no real answer. First, we are not talking about rare events but about an event we have never witnessed. Complete absence requires a better explanation.

Second, being more advanced or complex would not necessarily give preexisting life forms an advantage. Viruses, after all, fell humans worldwide, despite our best efforts.

But give these researchers full marks for bravado.

See also: Researchers: Water-based life could get started randomly on Earth if we leave out the water

Should we look for alien life that doesn’t need oxygen? Mustn’t put all our eggs in one basket? But there are no eggs. There is no basket. At this point, now that SETI is uncertain about even looking for intelligence as such, it is not clear what we are looking for or why. They now say that really good space alien technology would appear to be just nature.  So why might not ET life forms appear to be just rocks?

Experimental physicist Rob Sheldon on the recent merely “plausible” origin of life find

Steve Benner: Origin of life field beset by shortage of ideas, science by overflow of consensus


What we know and don’t know about the origin of life

THE RNA WORLD, AND THE ORIGINS OF LIFE http://reasonandscience.heavenforum.org/t2024-the-rna-world-and-the-origins-of-life The RNA world hypothesis, to be true, has to overcome major hurdles: 1. Life uses only right-handed RNA and DNA. The homochirality problem is unsolved. This is an “intractable problem” for chemical evolution 2. RNA has been called a “prebiotic chemist's nightmare” because of its combination of large size, carbohydrate building blocks, bonds that are thermodynamically unstable in water, and overall intrinsic instability. Many bonds in RNA are thermodynamically unstable with respect to hydrolysis in water, creating a “water problem”. Finally, some bonds in RNA appear to be “impossible” to form under any conditions considered plausible for early Earth. In chemistry, when free energy is applied to organic matter without Darwinian evolution, the matter devolves to become more and more “asphaltic”, as the atoms in the mixture are rearranged to give ever more molecular species. In the resulting “asphaltization”, what was life comes to display fewer and fewer characteristics of life. 3. Systems of interconnected software and hardware like in the cell are irreducibly complex and interdependent. There is no reason for information processing machinery to exist without the software and vice versa. 4. A certain minimum level of complexity is required to make self-replication possible at all; high-fidelity replication requires additional functionalities that need even more information to be encoded 5. RNA catalysts would have had to copy multiple sets of RNA blueprints nearly as accurately as do modern-day enzymes 6. In order a molecule to be a self-replicator, it has to be a homopolymer, of which the backbone must have the same repetitive units; they must be identical. On the prebiotic world, the generation of a homopolymer was however impossible. 7. Not one self-replicating RNA has emerged to date from quadrillions (10^24) of artificially synthesized, random RNA sequences. 8. Over time, organic molecules break apart as fast as they form 9. How could and would random events attach a phosphate group to the right position of a ribose molecule to provide the necessary chemical activity? And how would non-guided random events be able to attach the nucleic bases to the ribose? The coupling of a ribose with a nucleotide is the first step to form RNA, and even those engrossed in prebiotic research have difficulty envisioning that process, especially for purines and pyrimidines.” 10. L. E. Orgel: The myth of a self-replicating RNA molecule that arose de novo from a soup of random polynucleotides. Not only is such a notion unrealistic in light of our current understanding of prebiotic chemistry, but it should strain the credulity of even an optimist's view of RNA's catalytic potential. 11. Macromolecules do not spontaneously combine to form macromolecules 125. The transition from RNA to DNA is an unsolved problem. 13. To go from a self-replicating RNA molecule to a self-replicating cell is like to go from a house building block to a fully build house. 14. If two amino acids are located within the peptidyl transferase center, they will easily form a peptide bond. But as soon as you do that in the absence of the ribosome, the ends of the amino acids come together, forming a cyclic structure. Polymers cannot form. But if the ends are kept apart, by a theoretical primitive ribosome, a chain of peptide bonds could grow into a polymer. 30 15. Arguably one of the most outstanding problems in understanding the progress of early life is the transition from the RNA world to the modern protein based world. 31 16. It is thought that the boron minerals needed to form RNA from pre-biotic soups were not available on early Earth in sufficient quantity, and the molybdenum minerals were not available in the correct chemical form. 33 Otangelo Grasso
So, given only ID, what would be the necessary consequences for the current state of the system if it were true? What do I mean when I say "only ID"? I'm referring to being limited to ID the supposedly "official" scientific theory, as opposed to your personal view of ID. What can you actually conclude, necessary? The list will be very very short. IOW, you won't be able to get much of anywhere from there, without making assumptions that are simply not present in ID the actual theory itself. critical rationalist
According to SETI, "They now say that really good space alien technology would appear to be just nature." Unless life on earth is somehow an exception, this appears to be an admission that the information technology we find in DNA qualifies as the product of an intelligent agency. Whether the cause was by "space aliens" is another matter, but it can't be grounded in an infinite regress of "natural" causes. Scotoma
I guess it depends on what they consider to be complex molecules. Crystals can form very complex designs and, if you stretch the definition of self-replicating, they might meet this definition. But would we consider things like water molecules to be complex? I doubt it. Molson Bleu
The whole argument seems to be, "It could have happened, therefore it did." EvilSnack
We set up a general model
Well that clinches it, by Jove. Pop the champagne. /sarc Andrew asauber
"complex self-replicating molecules can emerge spontaneously and relatively easily from simple chemical reaction systems through a sequence of transitions." Then it should be relatively easy to demonstrate this in a lab. Show me. aarceng
Simply, show it. kairosfocus

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