RNA Is The Embodied Information That Sets Causal Boundary Conditions
axial | Schrödinger won the Nobel Prize in Physics in 1933 and was exiled from his native home Austria after the nation was annexed by Nazi Germany. He moved to Ireland after he was invited to set up the Dublin Institute of Advanced Studies. This follows the past history of Ireland acting as a storehouse of knowledge during the Dark Ages. After decades of work, biology was becoming more formalized around the 1940s. Better tools were emerging to perturb various organisms and samples and the increasing number of discoveries was building out the framework of life. With the rediscovery of Mendel’s work on genetics, scientists probably most importantly Thomas Hunt Morgan and his work on fruit flies (Drosophila) set up the rules of heredity - genes located on chromosomes with each cell containing a set of chromosomes. In 1927, a seminal discovery was made that irradiation by X-rays of fruits flies can induce mutations. Just the medium was not known where Schrödinger was thinking through his ideas on biology. At the same type, organic chemistry was improving and various macromolecules in the cell such as enzymes were being identified along with the various types of bonds made. For Schrödinger, there were no tools to characterized these macromolecules (i.e. proteins, nucleic acids) such as X-ray crystallography. Really the only tool useful at the time was centrifugation. At the time, many people expected proteins to be the store and transmitter of genetic information. Luckily, Oswald Avery published an incredible paper in 1944 that found DNA as probably the store instead of proteins.
With this knowledge base Schrödinger took a beginner’s mind to biology. In some ways his naivety was incredibly useful. Instead of being anchored to some widely-accepted premise that proteins transmitted genetic information (although he had a hunch some protein was responsible), the book thought from first principles and identified a few key concepts in biology that were not appreciated but became very important. Thankfully Schrödinger was curious - he enjoyed writing poetry and reading philosophy so jumped into biology somewhat fearlessly. At the beginning of the book, he sets the main question as:
“How can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry?”
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In the first chapter, Schrödinger argues that because organisms have orderly behavior they must follow the laws of physics. Because physics relies on statistics, life was follow the same rules. He then argues that because biological properties have some level of permanence the material that stores this information then must be stable. This material must have the ability to change from one stable state to another (i.e. mutations). Classical physics is not very useful here, but for Schrödinger his expertise in quantum mechanics helped determine that these stable states must be held together through covalent bonds (a quantum phenomena) within a macromolecule. In the early chapters, the book argues that the gene must be a stable macromolecule.
Through discussion around the stability of the gene, the book makes its most important breakthrough - an analogy between a gene and an aperiodic crystal (DNA is aperiodic but Schrödinger amazingly didn’t know that at the time): “the germ of a solid.” Simply, a periodic crystal can store a small amount of information with an infinite number of atoms and an aperiodic crystal has the ability to store a near infinite amount of information in a small number of atoms. The latter was more in line with what the current data suggested what a gene was. Max Delbrück had similar ideas along with J.B.S. Haldane, but the book was the first to connect this idea to heredity. But readers at the time and maybe even still overextended this framework to believe that genetic code contains all of the information to build an organism. This isn’t true, development requires an environment with some level of randomness.
GOD Must Be Small In Size And Permanent In Time
wikipedia | In chapter I, Schrödinger explains that most physical laws on a large scale are due to chaos on a small scale. He calls this principle "order-from-disorder." As an example he mentions diffusion, which can be modeled as a highly ordered process, but which is caused by random movement of atoms or molecules. If the number of atoms is reduced, the behaviour of a system becomes more and more random. He states that life greatly depends on order and that a naïve physicist may assume that the master code of a living organism has to consist of a large number of atoms.
In chapter II and III, he summarizes what was known at this time about the hereditary mechanism. Most importantly, he elaborates the important role mutations play in evolution. He concludes that the carrier of hereditary information has to be both small in size and permanent in time, contradicting the naïve physicist's expectation. This contradiction cannot be resolved by classical physics.
In chapter IV, Schrödinger presents molecules, which are indeed stable even if they consist of only a few atoms, as the solution. Even though molecules were known before, their stability could not be explained by classical physics, but is due to the discrete nature of quantum mechanics. Furthermore, mutations are directly linked to quantum leaps.
He continues to explain, in chapter V, that true solids, which are also permanent, are crystals. The stability of molecules and crystals is due to the same principles and a molecule might be called "the germ of a solid." On the other hand, an amorphous solid, without crystalline structure, should be regarded as a liquid with a very high viscosity. Schrödinger believes the heredity material to be a molecule, which unlike a crystal does not repeat itself. He calls this an aperiodic crystal. Its aperiodic nature allows it to encode an almost infinite number of possibilities with a small number of atoms. He finally compares this picture with the known facts and finds it in accordance with them.
In chapter VI Schrödinger states:
...living matter, while not eluding the "laws of physics" as established up to date, is likely to involve "other laws of physics" hitherto unknown, which however, once they have been revealed, will form just as integral a part of science as the former.
He knows that this statement is open to misconception and tries to clarify it. The main principle involved with "order-from-disorder" is the second law of thermodynamics, according to which entropy only increases in a closed system (such as the universe). Schrödinger explains that living matter evades the decay to thermodynamical equilibrium by homeostatically maintaining negative entropy in an open system.
In chapter VII, he maintains that "order-from-order" is not absolutely new to physics; in fact, it is even simpler and more plausible. But nature follows "order-from-disorder", with some exceptions as the movement of the celestial bodies and the behaviour of mechanical devices such as clocks. But even those are influenced by thermal and frictional forces. The degree to which a system functions mechanically or statistically depends on the temperature. If heated, a clock ceases to function, because it melts. Conversely, if the temperature approaches absolute zero, any system behaves more and more mechanically. Some systems approach this mechanical behaviour rather fast with room temperature already being practically equivalent to absolute zero.
Schrödinger concludes this chapter and the book with philosophical speculations on determinism, free will, and the mystery of human consciousness. He attempts to "see whether we cannot draw the correct non-contradictory conclusion from the following two premises: (1) My body functions as a pure mechanism according to Laws of Nature; and (2) Yet I know, by incontrovertible direct experience, that I am directing its motions, of which I foresee the effects, that may be fateful and all-important, in which case I feel and take full responsibility for them. The only possible inference from these two facts is, I think, that I – I in the widest meaning of the word, that is to say, every conscious mind that has ever said or felt 'I' – am the person, if any, who controls the 'motion of the atoms' according to the Laws of Nature". Schrödinger then states that this insight is not new and that Upanishads considered this insight of "ATHMAN = BRAHMAN" to "represent quintessence of deepest insights into the happenings of the world." Schrödinger rejects the idea that the source of consciousness should perish with the body because he finds the idea "distasteful". He also rejects the idea that there are multiple immortal souls that can exist without the body because he believes that consciousness is nevertheless highly dependent on the body. Schrödinger writes that, to reconcile the two premises,
The only possible alternative is simply to keep to the immediate experience that consciousness is a singular of which the plural is unknown; that there is only one thing and that what seems to be a plurality is merely a series of different aspects of this one thing…
Any intuitions that consciousness is plural, he says, are illusions. Schrödinger is sympathetic to the Hindu concept of Brahman, by which each individual's consciousness is only a manifestation of a unitary consciousness pervading the universe — which corresponds to the Hindu concept of God. Schrödinger concludes that "...'I' am the person, if any, who controls the 'motion of the atoms' according to the Laws of Nature." However, he also qualifies the conclusion as "necessarily subjective" in its "philosophical implications". In the final paragraph, he points out that what is meant by "I" is not the collection of experienced events but "namely the canvas upon which they are collected." If a hypnotist succeeds in blotting out all earlier reminiscences, he writes, there would be no loss of personal existence — "Nor will there ever be."[8]
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