In my previous blog, there were some issues that I want to address here. I edited it in order to correct some grammatical errors, hopefully making it more readable that way. For example, I wasn't aware of the fact that "information" is uncountable noun in English, unlike in Croatian, in which the word "informacija" has singular and plural form, since it means a piece of information, or a bit of information. Worse than that, I realized that I didn't properly mention authors of all papers that I referenced, so I corrected that, and I apologize for that too. I noticed also some logical errors, that I left as they are, but I will comment on them here.
When I said there that we identify cell with proteins (although, a cell is much, much more complex object than any of its protein parts, and its behaviour is probably not reducible to their behaviour), because these molecules are its most active part, I didn't emphasize enough that point, or finalize it by saying that both C(copier) and B(constructor), parts of V(vehicle), are proteins, mainly.
"The difference between the programmable and a simple constructor which can perform only elementary tasks, is that the latter works spontaneously only on a ground of physical laws that do not require information, while the former requires information on top of that,..."
also contain some nonsense, I cannot tell, because I didn't study constructor theory of information to that extent, to be sure that I can give precise and rigorous mathematical characterization of both types of constructors, and of the term "spontaneous". In other words, does spontaneous physical process mean it's possible without constructor, and does spontaneous action of a constructor mean it's possible without instructor(replicator)? Anyway, constructor theory is not about constructors, so maybe there is no such thing in these research papers. Still, the interesting question to me is (probably because I didn't study it properly, and definitely because of mr Deutsch's intervention), if there is a precise mathematical description of what does programmable constructor do to the information contained in a replicator, what information does it contribute in the act of construction, in comparison with what is contributed by the replicator(instructor)? Or, how actually is information contained in DNA molecule unpacked to produce the whole organism in all its complexity. One part of the answer are transcription and translation, and the other part is numerous copying of DNA during numerous cell cycles in an organism, and silencing certain of its parts during cell's differentiation. DNA contains certain redundancy neccessary for these repetitive tasks to be performed reliably and accurately. DNA replication and DNA repair beforehand, both use it to prevent mutations. Without that redundancy, compression would be even higher, but unreliable. So, there are two things opposing each other, data compression is a way to reduce or eliminate unwanted redundancy in data, while adding certain amount of desired redundancy elements serves for purposes of error detection.
But, what was my previous blog all about? First of all, ontological question about the origin of information may seem inappropriate, if there is a rigorous axiomatic theory already developed, that in terms of pure logic and intuition explains everything about that subject, unless one does not equal ontology and mathematics, and I do a bit, just like Alain Badiou does, so I don't consider such question inappropriate. Even if a little bit of mistery is desirable for science to flourish, one should not exaggerate and seek for a mistery where there is none, since after all, I'm interested in mathematics and physics of information, and not metaphysics. So I went back to study it more carefully, by reading other constructor theory research papers, primarily Constructor Theory of Information, which seems to be fundamental, as its content is repeated and referenced in others. What first struck my attention is this sentence:
"Any number of instances of any information medium, with any one of its information-instantiating attributes, is preparable from naturally occurring substrates."
I think there is an unnecessary redundancy here, because, there is already a definition of substrates given previously in the same paper:
"Constructor theory describes the world in terms of transformations involving two kinds of systems, playing different roles. One is the object causing the transformation, which we refer to as the constructor, and whose defining characteristic is that it remains unchanged in its ability to cause the transformation again. The other is the system being transformed, which may consist of one or more subsystems, the substrates."
I think that already defines substrates sufficiently as "naturally occuring" objects, since every object that occurs in the world is natural. If we explicitly state that fact, then we must allow for some alternatives here, because, from the same paper:
"this word ‘information’ in communication theory relates not so much to what you do say, as to what you could say…."
So, what else could you say there besides "naturally occuring"? "Artificially occuring", "supernaturally occuring", ...? There must be something for that phrase to convey any kind of information or meaning. It is mentioned in a sentence that defines one of conjectured principles of physics bearing on information, in a way as if it has some important meaning. There is a continuation:
"We call such substrates, which must therefore exist in unlimited numbers, ‘generic resources’."
So, what kind of definition of ‘generic resources’ is this? These are "naturally occuring substrates that exist in unlimited numbers, from which information medium is preparable"? Does it imply that information medium is "artificially occuring" if it has any one of its information-instantiating attributes already set (by an intelligent agent)? It shouldn't be, as I believe that intelligent agent is as natural as non intelligent ones. Besides that, generic resources are represented with a character "N", which stands for "Nutrients", that is amino acids and nucleotides, do they have a special role in constructor theory of life, or any naturally occuring substrates from which information medium is preparable, can play the same role of 'generic resources', such as magnetic tape, compact disc, or simply a stone or a tree into which one can carve one's own name?
I am not certain also if saying that abiogenesis was a task, is OK or not. Because, if it was a task, then in regardless of how many subtasks it could have been decomposed to, it should have been performed by some constructors. If however self-reproducing molecular machines arose from generic resources spontaneously, then it was not a task performed by constructors, but a spontaneous physical process.
To illustrate how vague is the term "spontaneous" in that theory, let's see some examples of its usage:
1.
"Generic resources can only perform a few tasks, only to a finite accuracy, called elementary tasks. These are physically simple and contain no design (of biological adaptations). Familiar examples are spontaneous, approximately self-correcting chemical reactions, such as molecules "snapping" into a catalysts regardless of any original small mismatch"
2.
"Very few such transformations happen spontaneously; that is to say, almost all require a constructor, which I shall define as anything that can cause transformations in physical systems without undergoing any net change in its ability to do so. I shall call those physical systems the constructor’s substrates"
3.
"Note, however, that the recipe is in one sense incomplete: as remarked in section 3.1, the recipe is not required to include instructions for the elementary tasks, which occur spontaneously in nature."
That's why it is hard for me to understand what does that theory say about classification of all physical processes into three types according to the constructor involved (programmable, not programmable, none), what is spontaneous and what is not, what is naturaly occuring and what is artificial, etc. I also don't understand why there is no uniformity throughout papers about what specifies physical process (transformation). Somewhere it is the input and output state of substrates, somewhere it's input and output attributes of substrates. It obviously doesn't matter, but it gives an impression of inconsistency.
Also, maybe my attempt to draw a conclusion about classification of physical processes, based on a number of objects involved and their activity vs passivity is also naive. Let's compare physical transformations to financial transactions that we usually do. For example, I just bought some staff in a grocery store near me, and thought about the cashier, what changes does she undergo during the transaction, and her ability to do same things again after serving me. So, what roles are involved in that transaction, and to what extent are they active or passive?
goods bought = passive
buyer = active transaction initiator, financially debited in return for goods
cashier = active in assisting the transaction, gets salary, otherwise passive
merchant = active in providing a point of sale, gets margin/fee, otherwise passive
state = active in providing cash as a means of payment, gets tax, otherwise passive
bank = active in providing money account and card, if card is used, gets fee, otherwise passive
OK, so is there any analogy between physical transformations and financial transactions?
There was an important question about how the evolution actually works, ie what is the motor of genetic changes throughout the history of living organisms. And I didn't mention another factor, called speciation. This lineage-splitting event occurs when there is at the beginning a compact population of genetically compatible entities which can interbreed in the whole domain of their habitat, and then for some reason occurs reproductive isolation between certain parts of population, so that they actually become separated and genetically distant and evolve to the point when members of different subpopulations become genetically incompatible, ie different species. There is also a scenario of ring species, where genetic distance between adjacent subpopulations is not significant, and they can interbreed, but between distant subpopulations it is significant, even though they may due to the closure of the ring eventually become geographically near, they remain genetically distant. So, the splitting in that case is blur. But in any case, such manifestations on a macroscopic scale are caused on microscopic scale mainly by recombination of parental genes during sexual reproduction over generations, which usually leads to non significant branching and merging of evolutionary tree. It is highly unlikely that such processes, which could split for example Equus genus into horse, donkey and zebra lineages, could ever lead to changes such as for example those that happened when organisms that had gills and lung developed from those that only had gills, because that requires substantially different type of change. Not to mention that if this factor was the only motor of evolution, it would be impossible for species that reproduce asexually to evolve at all. It is interesting that a genetic compatibility between horses and donkeys is such that they can produce viable, but infertile offspring, due to a large genetic distance, which characterizes outbreeding. Opposite situation occurs in small isolated communities, which are vulnerable to inbreeding depression, such as island of Susak where children with Down syndrome were frequent. Favourable is crossbreeding between subpopulations with moderate genetic distance, since it often has the most positive effects on fitness-related traits, and human species subpopulations throughout history were reproductively isolated to the extent of appearance of several races that are genetically distant in precisely that moderate way. Due to a globalization, merging into a single human race is what is actually going on.
Some dude called Moontanman on a science forum: topic african lungfish circulatory system warned me about Gene duplication, as a possible answer to my question, which is how does evolution work. This is still a result of random action of various agents, although maybe not a typical damage that usually results from such actions.
But I still don't get it how abiogenesis happened, and how does evolution work.
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