Physics and biosemiotics

Vasily Ogryzko

1 Information and Physics

It is my firm opinion that modern physics is moving toward a new paradigm, with the concepts of "information" and "meaning" assuming a fundamental role, equal to the one which is now played by such concepts as "energy" and "field". Biosemiotics, as the science of symbolic systems in living nature, will be of crucial importance in this process. Physics is already familiar with the concept of information, due to the development of the statistical foundation of thermodynamics and quantum mechanics. The paradox of Maxwell demon from statistical mechanics and the problem of observer in quantum theory are the most obvious examples of this familiarity.

Recently, an interesting volume called Complexity, entropy and information, (ed. by W. H. Zurek) came out. The idea of information and its links to physics (entropy and quantum mechanics) is explored by different authors in this book. J. A. Wheeler, in the first chapter of the book, proposed a concept "it from bit", which "...symbolize the idea that every item of the physical world has at bottom, at a very deep bottom, an immaterial source and explanation, in short that all things physical are information-theoretic in origin".

However, despite the fact that physics is indeed approaching the concept of information as something of fundamental importance, I believe that as long as the physics deals with nonanimate nature, these new ideas will be mostly neglected by working physicists, who are not very concerned with deep philosophical issues. The reason for this is the following: when we are in the field of nonanimate objects, the concept of information comes as a primarily epistemiological tool, which refers to our own (as observers) way of describing nature, and not as something belonging to the world itself.

So far physicists have managed to describe their phenomena using deterministic and reversible fundamental equations; they consider their objects either as isolated systems, or as interacting with their environment in a random manner. Hence, only the most trivial, quantitative ("Shannonian") aspect of the information concept has been exploited, leaving aside issues of value and meaning of information. Even in the case of quantum mechanics, the great success of this theory was due precisely to the ability of its founders to separate the comprehensible part of phenomena and describe it using reversible deterministic equations (for example, Shroedinger equation). All the dangerous questions about the role of the observer, irreversibility, reduction of wave function, etc. were combined together under the name of measurement problem and left out of brackets, for future generations to resolve. In any case, whenever the information concept has been used, it was used as an epistemiological tool.

It is only when one enters the domain of biology, that the phenomenon of information starts to play a role independent from us; it belongs to the world itself. Life has been using genetic information for millions of years before we existed. Living things can be understood as observers accumulating knowledge about the outside world during their adaptive evolution, and then processing and propagating this knowledge for their needs. This view turns the phenomena of information into an objective characteristic of reality, having not only a shannonian but also a semiotic dimension, absent in the physics of inanimate matter. That is why biology and especially biosemiotics is so important for the foundation of the new paradigm mentioned above.

No doubt, semiotics is even more crucial in humanitarian studies. Biology, however, has an edge to be closer to hard sciences, and a greater chance to be the first discipline to be united with physics.

2 Nonreductionist physicalism

Before this unification can occur, some reconstruction of the biological house should be done. First of all, biology should overcome the reductionist character of its methodology. As the pacesetter in the life sciences is molecular biology, whose reductionistic approach has always been based on the application of physicalist methodology, the claim that the unification of physics with biology will require giving up reductionism, may seem paradoxical. However, nonreductionist physicalism is quite possible: the quantum-mechanical principle of nonseparability demonstrates that physics has come close to overcoming one of the basic principles of reductionism: "the whole is just a sum of its parts". In short, the principle of nonseparability says that knowledge of the state of a complex system does not always require the exact knowledge of the state of its parts: in fact, the parts may be in a less definite (mixed) state than the whole.

It is molecular biology which is the stronghold of the reductionist methodology in science. Here are several factors contributing to this conservative state of affairs.

1. Molecular biology is still in the descriptive stage of its development as a science. There are two main reasons for this:
a. The object of study is much more complex than that of physics. There is not enough data to build sensible theories and conclude that reductionism does not work.
b. Huge variety of objects. After one object has been described, there is another one to describe.

2. Aesthetical and political rather than logical criteria play a more important role in molecular biology compared to physics. There are again two reasons for this:
a. Complex object of study. Criteria of excluded third and verification (falsification) are less valuable compared to physics due to the large possibility of using ad hoc hypotheses. Since molecular biology is currently charmed by reductionism, this has precluded any serious hopes for antireductionism so far.
b. The progress in molecular biology to date has been due to predominantly experimental work, with results produced not by an individual scientist but by collectives. Hence - the role of organizing authority and of power play.

3 Quantum mechanical approach to adaptation

One of the focal points in the new interaction between physics and biology is going to be the concept of adaptation. Physics can provide a nonreductionist approach to this concept.

What does adaptation have to do with semiotics? When it comes to biology, the relation is quite straightforward, due to the obvious pragmatical (or rather, axiological) aspect of biological information. One may argue about what exactly is the meaning of a gene; however, everyone agrees that any genetic information exists because it has an adaptive value. Even junk DNA which has no phenotypic effect whatsoever has a value for itself. Value, pragmatic aspect seems to be more fundamental than semantic aspect of a biological sign.

Nowadays all biology is baptized in Darwinism, which explains all adaptation by natural selection. There is however, a more naive, "pagan" idea of adaptation which does not imply Darwinian selection at all. Importantly, it can be applied even to inanimate systems. The simplest example is water adapting to the shape of the vessel. This phenomenon is governed by the principle of energy minimum, which itself has been a subject for the teleological interpretations for a long time.

It is interesting to note, that on a fundamental level, the concept of selection can underly the pagan adaptation as well: quantum-mechanical states are selected that are either eigenfunctions of the energy operator or of an observable operator, depending what situation one is considering. Again, only the "fitted" variants survive in both of these cases, all others being destroyed by interference. However, there is an important difference from the Darwinian case: the selected variants do not preexist independently from each other prior to selection, they are all "parts" (components) of one state. Therefore, in spite of selection involved, this kind of adaptation can be considered lamarkian as well.

In 1991, I (Ogryzko V., 1991) proposed to use this idea for the explanation of the phenomenon of directed mutations in bacteria which recently attracted the attention of biologists (Cairns et al. 1988). Obviously, it can be expanded to other cases of biological adaptation as well. Moreover, I believe that ultimately it can help us to understand how the values and meaning of the human signs emerge.

References

Cairns, J., J. Overbaugh and S. Miller1988 The Origin of Mutants, Nature, 335: 142-145
Ogryzko Vasily 1991 A quantum-mechanical approach to the phenomena of directed mutations in bacteria (unpublished)
Zurek, W. ed. 1990 Complexity, entropy, and the physics of information, Redwood City, Calif. : Addison-Wesley