Tuesday, 15 March 2016

The Evolution of Knowledge

John O. Campbell
 
This is an excerpt from the book: Einstein's Enlightenment.

John A. Wheeler, one the greatest American physicists of the twentieth century, reminisced that his career had unfolded through three fundamental paradigms  (1):

I think of my lifetime in physics as divided into three periods. In the first period, extending from the beginning of my career until the early 1950's, I was in the grip of the idea that Everything Is Particles. I was looking for ways to build all basic entities - neutrons, protons, mesons, and so on - out of the lightest, most fundamental particles, electrons, and photons. …

I call my second period Everything Is Fields. From the time I fell in love with general relativity and gravitation in 1952 until late in my career, I pursued the vision of a world made of fields, one in which the apparent particles are really manifestations of electric and magnetic fields, gravitational fields, and space-time itself.

Now I am in the grip of a new vision, that Everything Is Information. The more I have pondered the mystery of the quantum and our strange ability to comprehend this world in which we live, the more I see possible fundamental roles for logic and information as the bedrock of physical theory.

His experience may have been usual among physicist at the time but now our biggest quibble might be with his repeated use of the word ‘Everything’. Although it is almost universally conceded today that information has a profound role in the workings of the world, few would insist on a uniquely primary role. After-all the Large Hadron Collider (LHC), the premier experimental apparatus of an era, is understood largely in terms of particles and fields. These concepts have not been displaced from physics.

We might understand the ‘Everything’ as due to an excitement with novelty and the focus it commands. However, the real challenge of the information revolution is to develop a more prosaic understanding of the relationships among information and the other important physical entities.

Unfortunately, Einstein missed out on the last of these paradigms. The information revolution came upon us only since his death. He did however play a fundamental role in developing the first two paradigms. Atomic theory was accepted by many physicists, due to a paper Einstein wrote in his miracle year of 1905 on Brownian motion. He demonstrated that the precise microscopic jiggling observed of pollen grains floating in water could be explained using the atomic theory. This was sufficient to convince many of the existence of atoms and other types of fundamental particles. He also used an understanding of fields to assist in the construction of his general theory of relativity.

It is unfortunate that he missed out on information theory because it is likely that he would have put his own stamp on it by creating another elegant fundamental theory. One feature of information which would not have escaped him is that it describes an aspect of nature which seems non-materialistic. Many of history’s great thinkers have argued that there is more to nature than material or substances. Foremost in this list may be Plato, Spinoza, Peirce and Einstein. At last the introduction of information as a fundamental component of reality provides a means of framing some of their ideas in scientific terms.

Einstein’s understanding that (2):

the sublimity and marvelous order which reveal themselves both in nature and in the world of thought.

reveals that he sometimes considered nature to have properties akin to mind. This notion fit well with his belief, along with Spinoza, that God and nature are equivalent. In this view nature may more closely resemble God then material. Einstein might well have been open to any addition to the physicist’s conceptual toolkit which would support an alternative to strict materialism.  

The relationship between information and other aspects of reality appears to be a deep one and one that is only beginning to be explored. Although the information revolution has swept practically every scientific discipline, no widespread agreement has emerged that they are even taking about the same thing except at the most abstract level. For instance, few biologist or physicists have noted much similarity between the genome and the wave function.

In this section I will build on the explanation discussed earlier that information is only information if it informs something. That something is a model and when a model is informed by information or evidence it is updated so that its knowledge is increased. It is this knowledge which supports the existence of complex entities; the more complex the entity the more knowledge is necessary for its existence.

The mass of our solar system, including the sun, the planets and their moons total 1.0014 solar masses (3). In other words, the sun contains 99.9% of the of the matter in the solar system. Although the sun and other stars are complex entities ultimately responsible for forming all atoms more complex then helium, they are chemically quite simple; they are composed only of atoms. Stars are so hot that their atoms are ionized, they do not allow the binding of electrons to the atomic nucleus and they are far too energetic for even more complex chemical forms such as molecules.

Only in interstellar space and on those bodies orbiting stars, where temperatures are much cooler, can the delicate bonds joining atoms into molecules form. Even then, naturally-occurring inorganic molecules seldom combine more than a hundred atoms. Only in exceptionally rare circumstances does even this level of chemical complexity exist. In the end the complexity of chemical forms is governed by quantum forces, chemical structures are constrained to those quantum possibilities which environmental circumstances allow.

Central to the evolution of life was the invention of chemical forms orders of magnitude more complex. Indeed, the essence of life is its ability to design and choreographer intricate chemistry. Organisms are only chemistry, but an astonishingly complex chemistry, one which, as far as we know, does not exist anywhere else in the universe. Organic molecules may be composed of almost a million atoms. Life’s ability to achieve this amazing leap in complexity does not violate chemistry’s quantum laws, rather it achieves this complexity by placing chemistry in unique circumstances or environments which resemble chemical factories. Many fundamental chemical reactions carried out in these ‘factories’ employ organic catalysts known as enzymes. These molecules, may for example, bind to one or more ‘substrate’ molecules and cause them to participate in chemical reactions that would not be possible without the action of the enzyme. In this manner enzymes control much of the specialized chemical pathways which take place in living things. As Wikipedia describes this process (4):
Enzymes accelerate, or catalyze, chemical reactions. The molecules at the beginning of the process are called substrates and the enzyme converts these into different molecules, called products. Almost all metabolic processes in the cell need enzymes in order to occur at rates fast enough to sustain life. The set of enzymes made in a cell determines which metabolic pathways occur in that cell. Enzymes are known to catalyze more than 5,000 biochemical reaction types

Even this wizardry of enzymes cannot defy physics, and in many biochemical reactions the products are more energetic than the substrate from which they were formed; physics requires an input of energy. The means of supplying this energy is the same in all types of life, and involves another enzyme: ATPase. This enzyme uses the energy rich molecule ATP as a substrate to inject energy into reactions involving other substrates (5):

ATPases are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion. This dephosphorylation reaction releases energy, which the enzyme (in most cases) harnesses to drive other chemical reactions that would not otherwise occur. This process is widely used in all known forms of life.

Again the energy of ATP must come from somewhere and that somewhere is a subcellular body called a mitochondrion. Each biological cell contains hundreds or thousands of mitochondria which function to convert the energy from food into the electro-chemical energy of the ATP molecule. Mitochondria create an electric polarization by pumping protons across an impermeable membrane, and use this to energize ATP molecules which, in turn, may be used to perform biological work under the direction of ATPase enzymes.

Our bodies process 50 to 75 kilograms of ATP a day; each molecule is recycled and reenergized over 500 times. The stunning magnitude of the process is made even starker if we consider the rate at which our bodies must pump individual protons across mitochondrial membranes. As the bio-chemist Nick Lane explains (6):

Their job is to pump protons, and together they pump more than 1021 of them – nearly as many as there are stars in the known universe – every second.

I have attempted to hint at the mind-boggling jump in complexity which biological processes have achieved over inorganic chemical processes. This complexity is largely due to genetic design which, in turn, has evolved continuously since the first life. It is this genetic knowledge which allows the complex chemistry which is life to exist.

Biological evolution is an interplay involving genetically recorded knowledge and the environment in which it finds itself.  The knowledge is of designs for individual organisms which may have an existence in that environment. It is also knowledge for the execution of those designs and the construction or development of individuals from that knowledge. The differential success in maintaining an existence enjoyed by the individuals of each generation is the information which updates the knowledge repository as to what works and what doesn’t. This is a basic form of the evolution of evidence-based knowledge.

The knowledge involved is extremely specific. For example, each of the 5,000 enzymes which catalyze a chemical reaction pathway may be composed of up to 2,500 amino-acid building blocks and each of these building blocks is coded for by a 3-character sequence of DNA. Over evolutionary time small variations, in the form of mutations, may be introduced to this code and individuals with slightly unique enzymes are given an experimental try-out in the environment. The successes are recorded and live on within the species’ genome but the failures do not. In this manner knowledge of successful designs form powerful models and accumulate in the genome. Thus behind each of those vast number of enzymes is an informational plan for its structure, construction and use. In this instance the information is at least equally fundamental as is material in the form of the enzyme.

The entire realm of the biosphere is formed from the interactions among a vast number of experimental designs. Each of these individual organisms are mortal and have but a short life span; it is the knowledge repository or model from which they spring that is more nearly immortal. In this unusual perspective the vast system of interacting organisms composing the biosphere appears less significant than the timeless knowledge which forms them. As phenotypes, we strut and fret our hour upon the stage but these experiments in living may signify only little to the repository of enduring knowledge.

This view of a reality beyond materialism and the world of appearances is supported by a current scientific revolution in which information is understood as at least equally fundamental as mass and energy. It harkens back to Plato and his understanding that the world of appearances is but a shadow world, a mere reflection of an underlying realm of ‘ideas’.

The scientific duality of matter and information is deeply entwined; all information is recorded in material form and all matter is formed under the direction of information. Their relationship in our understanding is not an exclusive one where either matter of information will displace the centrality of the other, rather it is a synergy. This synergy appears to be the only method which nature has found capable of accumulating knowledge.

Science itself is a case in point. Although we normally take it for granted, the rise of science was one of the key moments in the history of both our species and of our planet. Agricultural science transformed the planetary landscape as it developed processes capable of feeding seven billion people. Geologists are about to name a new geological epoch, as the Anthropocene, the geological era in which human activity is the dominant force shaping our planet. As seen from space our planet is unique as the only one to shine the light of its own internally-generated energy.




This transformation of the planet by humans began long before the formal study of science but it may be argued that even those early forms of human knowledge owe their power to a vague similarity to refined science. For example, the transformation of the earth’s surface through agriculture, which began in a so-called prescientific era, undoubtedly occurred through a dynamic between human ideas of what might work and the retention of experimental evidence of what did work.

Among all organisms, humans are uniquely adapted to take nature’s ancient method of knowledge accumulation to a new level. Perhaps the most unique of our biological adaptations is our big brain. While much of our brain design is shared with closely related animals, our prefrontal cortex is hugely outsized. 

This is the section of the brain which supports imaginative and sometimes even rational thinking (7):

This brain region has been implicated in planning complex cognitive behavior, personality expression, decision making, and moderating social behaviour. The basic activity of this brain region is considered to be orchestration of thoughts and actions in accordance with internal goals.

A striking feature of our uniquely imaginative mind, despite its great power is its surprising lack of accuracy. We can imagine practically anything; our imaginations know no bounds. What use are such thoughts if they are likely wrong?


Fortunately, we have also inherited a sensory cortex that is little changed from of our near animal relatives. This part of the brain, which provides us with senses and perceptions, is an ancient one and has been evolving for hundreds of millions of years. Its purpose is to provide animals with accurate information about what is actually going on in the world around them. Poor experimental designs of this brain area are quickly erased from the evolutionary record and hence it now provides us with highly detailed, reliable and accurate models of reality.

Humans and other animals exploit a synergy between the abilities of the prefrontal and sensory cortexes. The prefrontal cortex can provide hypothetical models of what is going on in the world and these can be judged and selected using our accurate sensory information. This synergy is used for the purpose of ‘orchestration of thoughts and actions in accordance with internal goals’ but such resulting behaviours may be seen in terms of experiments; behavioural actions are attempts to achieve goals but are not always successful, hopefully we learn from the evidence of those successes and failures.

This is essentially nature’s ancient method of knowledge accumulation which has achieved new vistas with the substantial increase in power of the human prefrontal cortex. It is most highly refined in the practice of science. We learn scientific models from the community of past and present scientists. No two people have exactly the same models so there is some variation among them. These various models are tested by experiments which collect sensory evidence and this evidence is used to calculate the models’ relative plausibility in light of that evidence. The most plausible models are selected. This is exactly the Darwinian paradigm of heredity, variation and selection. Indeed, many philosophers of science describe science as a Darwinian process (8; 9; 10).

At the core of science is reproducible evidence. A new variation to a scientific model will only gain support if evidence, usually from experiments, is gathered, and it can be seen that the sum of the evidence more clearly supports the new model rather than the old. Scientific evidence must be reproducible by others to guard against the possible bias, errors or delusions of a single researcher. Evidence which may be freely reproduced can be considered a technology. For example, our cell phones may be considered as providing reproducible evidence; each time we use them and they work, we are adding support to the vast number of scientific models used in their design.

In this light the vast technological landscape we inhabit is similar to the biosphere; its members are short-lived experiments and are but the temporal expression of a more timeless process of knowledge accumulation.

While we might be willing to view our cultural and perhaps even our biological selves as material or substance orchestrated by an ancient knowledge, can we extend this paradigm to the mind-bending possibility that it also applies to physical reality itself?

At the basis of a scientific understanding of reality is the quantum/classical divide. Our best science tells us that at bottom there is only quantum phenomena yet our experience of the world is that it is almost exclusively classical. It turns out that quantum reality is vast and contains many possibilities such as things being both here and there at the same time which we never experience. We experience only a classical reality where things are either here or there. Classical reality is only an extremely small subset among the vast quantum possibilities. What makes it special and how is it selected as the physical reality we inhabit?

A leading authority on the nature of quantum interactions, Wojciech Zurek, has proposed an explanation he calls quantum Darwinism (11). In this theory classical reality is selected from the quantum possibilities through a Darwinian process.

To appreciate the significance of this theory, we should first consider that at the basis of a scientific understanding of reality is information exchange. The four fundamental forces of nature operate through the exchange of information. With forces, such as electro-magnetism, one entity provides information to another as to what it should experience, for example, how it should move. Without such forces or information exchange the most fundamental particles would be isolated and unable to bond to or have any effect on other particles. There would be no reality at all, in the sense of containing complex entities whose components have mutual information about one another, one which could come to know itself. It is only through the process of information exchange that reality exists, that any entity may experience a reality beyond itself.

In Zurek’s view the quantum nature of reality is constrained to isolated particles but when these particles pass information to entities in their environment it is only classical information which can survive and reproduce. As the nature of reality is dependent upon the information which is exchanged we experience only a classical reality.

The nature of the information which quantum system pass to their environments are in the form of hard physical facts including force, position and momentum. Our understanding of it may morph between considering it as information or as physical entity. Of course the type of information which may survive is highly dependent upon the environment, for example some environments may support information concerning position and others information concerning momentum.

At the core of quantum theory is the understanding that quantum reality is in the form of information. The quantum wave function is a knowledge repository which fully describes quantum entities and any information which may be received from it by any other entity is contained within the wave function. Quantum Darwinism demonstrates that the only type of information capable of surviving the rigors of transfer is classical information.

When information transfer occurs a remarkable transformation of the wave function takes place; it ‘jumps’ to a state that corresponds to the information it has transferred. Even though the information which was transferred may have been selected from a vast array of quantum possibilities, after the transfer the quantum possibilities are reduced to only that information. For example, if the information transfer takes the form of a measurement then quantum theory assigns a probability to each possible outcome. The actual outcome may have been assigned only a low probability. However, if another identical measurement is repeated immediately following the first, the same result is predicted with probability 1. Thus the updating of the quantum model keeps it in sync with the information transferred to the environment.

Another way of looking upon this is to view the information or physical entity which the quantum system transfers to its environment as an experiment designed to gather information concerning its environment and the forms which may survive there. This evidence then updates the knowledge repository of the wave function. In the light of quantum Darwinism those forms which can survive also do evolve, quarks evolve into nucleons, nucleons into atoms and atoms into molecules. At each step the quantum wave function is the knowledge repository which continuously explores environmental possibilities through experimental probes.

Again we have the same paradigm, this time portraying the fundamental physical constituents of the universe, such as quarks, atoms and molecules, in terms of short lived experimental probes which update a more timeless knowledge repository as to what can exist.

Bibliography

1. Wheeler, John A. Geons,black holes & quantum foam. [ed.] Kenneth Ford Norton. 1998.
2. Einstein, Albert. Science and Religion. s.l. : New York Times magazine, http://www.sacred-texts.com/aor/einstein/einsci.htm, 1930.
3. Wikipedia. Solar System. Wikipedia. [Online] https://en.wikipedia.org/wiki/Solar_System.
4. —. Enzyme. Wikipedia. [Online] https://en.wikipedia.org/wiki/Enzyme.
5. —. ATPaes. Wikipedia. [Online] https://en.wikipedia.org/wiki/ATPase.
6. Lane, Nick. The Vital Question. s.l. : W. W. Norton & Company, 2015. ASIN: B00OD8Z4JW.
7. Wikipedia. Prefrontal cortex. Wikipedia. [Online] https://en.wikipedia.org/wiki/Prefrontal_cortex.
8. Blind variation and selective retension in creative thought as in other knowledge processes. Campbell, Donald T. 1960, Psychological Review, Vol. 67, pp. 380 - 400.
9. Popper, Karl. Objective Knowledge. s.l. : Claredon Press, 1972.
10. Hull, David L. Science as a Process: An Evolutionary Account of the Social and Conceptual Development of Science. Chicago and London : The University of Chicago Press, 1988.
11. Quantum Darwinism. Zurek, Wojciech H. s.l. : http://www.nature.com/nphys/journal/v5/n3/abs/nphys1202.html, 2009, Nature Physics, vol. 5, pp. 181-188.
12. Ford, Kenneth. John Archibald Wheeler: Doer and Visionary. s.l. : As viewed on http://www.metanexus.net/magazine/ArticleDetail/tabid/68/id/5491/Default.aspx September 24, 2010, 2010.


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