Information and the Nature of Reality
From Physics to Metaphysics
ed. Paul Davies/Niels Gregersen
Oxford 2010

1 Davies/Gregersen: Does information matter?
Inherited notions of matter and the material world have not been able to sustain the evolutionary development of 20th century physics and biology.
For centuries Jsaak Newton's idea of matter as consisting of „solid, massy, hard, impenetrable, and immovable particles“ reigned in combination with a strong view of laws of nature that were supposed to prescribe exactly, on the basis of the present physical situation, what was going to happen in the future. This complex of scientific materialism and mechanism was easily amalgamated with commonsense assumptions of solid matter as the bedrock of all reality. Complex systems such as living organisms, societies, and human persons, could, according to this reductionist worldview, ultimately be explained in terms of material components and their chemical interactions.

However, the emergence of thermodynamics began to cast doubt on the universal scope of determinism. It was not until the 20th century, however, that the importance of non-equilibrium dissipative structures in thermodynamics led scientists (Ilya Prigogine) to formulate a more general attack on the assumptions of reversibility and scientific determinism.

Three new developments of 20th century physics in particular force the downfall of the inherited Matter Myth, and lead to new explorations of the seminal role of information in physical reality: Einstein's theory of general relativity, quantum theory (which describes a fundamental level of reality), and information.

3… Davies, Lloyd and Stapp §challenge some widely held assumptions about physical reality. Davies asks what happens if we do not assume that the mathematical relations of the so-called laws of nature are the most basic level of description, but rather if information is regarded as the foundation on which physical reality is constructed. Davies suggests that instead of taking mathematics to be primary, followed by physics and then information, the picture should be inverted in our explanatory scheme, so that we find the conceptual hierarchy: information ------> laws of physics -------> matter.

4 In the absence of a functional quantum computer, the most powerful information-processing system known is the human brain (that may change soon, as even classical computers are set to overtake the brain in terms of raw bit flips).
The relationship between mind and brain is the oldest problem of philosophy, and is mirrored in the context of this volume by the information-matter dichotomy.
Crucially, the brain does more than flip bits. Mental information includes the key quality of semantics; that is, human beings derive understanding of their world from sense data, and can communicate meaning to each other.
The question here is what can, and what cannot, be explained merely by digital information, which is formulated in terms of bits without regard to meaning. When the foundation for information theory was laid down by Shannon, he purposely left out of the account any reference to what the information means, and felt solely on the dance mission aspects. His theory cannot, on its own, explain the semantics and communication of higher-order entities. At most, one could say, that Shannon focused on the syntactic features of an information potential. (cf. Deacon 146)

6 The incomplete nature of information theory is exemplified by several distinct meanings of the term „information“. Quantum events as informational qubits (Seth Lloyd) have a very different character from Shannon-type digital information, or mere patterns (Aristotelian information), and none of the foregoing can much illuminate the emerging concept of meaningful information (semantic information).

In spite of the tentative nature of the subject, however, two reasons can be offered for giving information the central role in the scientifically informed ontology. The main point is that information makes a causal difference to our world - something that is immediately obvious when we think of human agency. But even at the quantum level, information matters. It seems that just as informational events are quintessential at the lowest level of quantum reality, so are informational structures quintessential as driving forces of the hierarchical unfolding of physical reality.

65 Paul Davies Universe from bits

In the light of modern physics, apparently solid matter is revealed, on closer inspection, to be almost all empty space, and the particles of which matter is composed are themselves ghostly patterns of quantum energy, mere expectations of invisible quantum fields, or possibly vibrating loops of strings living in a ten-dimensional space-time.
The history of physics is one of successive abstractions from daily experience and common sense, into a counterintuitive realm of mathematical forms and relationships, with a link to the stark sense data of human observation that is long and often tortuous.
Yet at the end of the day, sciences empirical, and our finest theories must be grounded, somehow, „in reality“.
But wary is reality? Is it in the acts of observation of the world made by human and possibly nonhuman observers? In records stored in computer or lavatory notebooks? In some objective world „out there“? Or in a more abstract location?

75 It from bit

The traditional relationship between mathematics, physics, and information may be expressed symbolically as follows:

mathematics --------> physics ---------> information

According to this orthodox view, mathematical relationships are the most basic aspects of existence. Whereas information is a secondary, or derived, concept that characterizes certain specific states of matter (such as a switch being either on or off, or an electron spin being up or down).
However, an alternative view is gaining in popularity: a view in which information is regarded as the primary entity from which physical reality is built. It is popular among scientists and mathematicians who work on the foundations of computing, and physicists who work on the theory of quantum computation. Importantly, it is not merely a technical change in perspective, but represents a radical shift in a worldview, well captured by Wheeler‘s slogan „It from bits“. The variant I wish to explore here is to place information at the base of the explanatory scheme, thus:

Information -------> laws of physics ----------> matter

After all, the laws of physics are informational statements: they tell us something about the way the physical world operates. This shift in perspective requires a shift in the foundational question concerning the origin of the laws of physics; we may now ask about the origin and nature of the information content of the universe. (cf. Seth Loyd)

92 Seth Lloyd The computational universe:
We are in the midst of an information-processing revolution based on electronic computers and optical communication systems. This revolution has transformed work, education, and thought, and has affected the life of every person on earth.
The effect of the digital revolution on humanity as a whole, however, pales when compared with the effect of the previous information-processing revolution: the invention of movable type. The invention of the printing press was an information-processing revolution of the first magnitude. Movable type allowed the information in each book, once accessible only to the few people who possessed the book‘s hand-copied text, to be accessible to thousands or millions of people. The resulting widespread literacy and dissemination of information, completely transformed society. Access to the written word empowered individuals not only in their intellectual lives, but in their economic, legal, and religious lives as well.

Similarly, the effect of the printed word is small when compared with the effect of the written word. Writing - the discovery that spoken words could be put into correspondence with marks on clay, stone, or paper - was a huge information-processing revolution. The existence of complicated, hierarchical societies with extended division of labour depends crucially on writing.

Just as printing is based on writing, writing stems from one of the greatest information-processing revolution in the history of our planet: the development of the spoken word. Human language is a remarkable form of information-processing, capable of expressing, well, anything that can be put into words. Human language includes within it the capacity to perform sophisticated analysis, such as mathematics and logic, as well as the personal calculations that underlie the complexity of human society. Although other animals have utterance, it is not clear that any of them possess the same capacity for universal language that humans do. Ironically, the entities that possess the closest approximation to human language are our own creations: digital computers, whose computer languages possess a form of universality bequeathed to them by human language. It is the social organisation stemming from human language (together with the written language, the printed word, computers, etc) that have made human beings so successful as a species.

Before turning to even earlier information-processing revolutions, it is worth to saying a few words about how human language came about. Who discovered human language? Fossil skulls suggest that human brains underwent significant change over a period of time, with the size of the cortex expanding tenfold. The result was our species, Homo sapiens: „man with knowledge“ (literally, man with taste). 94 Once you can reason, there is great pressure to develop the form of utterance that embodies that reason. Groups of Homo sapiens who could elaborate their way of speaking to reflect their reasoning would have a substantial evolutionary advantage over other groups who were incapable of complex communication and who were therefore unable to turn their thoughts into concerted action.

95 The mother of all information-processing revolution is life itself. However it came about, the mechanism of storing genetic information in DNA, and reproducing the variation, is a truly remarkable invention that gave rise to the beautiful and rich world around us. Life is the original information-processing revolution. Or is it? Life arose on Earth sometime in the last five billion years. Meanwhile, the universe itself is a little less than fourteen billion years old. Were the intervening nine billion years completely devoid of information-processing revolutions? The answer to this question is „No“. Life is not the original information-processing revolution.

The very first information-processing revolution, from which all other revolution stem, began with the beginning of the universe itself. The big bang at the beginning of time consisted of huge numbers of elementary particles, colliding at temperatures of billions of degrees. Each of these particles carried with it bits of information, and every time two particles bounced off each other, those bits were transformed and processed. The big bang was a bit bang.Starting from its very earliest moments, every piece of the universe was processing information. The universe computes. It is this ongoing computation of the universe itself that gave rise naturally to subsequent information-processing revolutions such is life, sex, brains, language, and electronic computers.

96 the computational universe
102 It has been known since the end of the 19th century that if the universe can be regarded as a machine (the mechanistic paradigm), it is a machine that processes information. In the 1990s, researchers in quantum computation showed that the universe was capable of full-blown digital computation at its most microscopic levels: the universe is, technically, a giant quantum computer.
The computational paradigms for the universe supplements the ordinary mechanistic paradigm: the universe is not just a machine, it is a machine that processes information. The universe computes. The universe is a physical system that can be programmed at its most microscopic level to perform universal digital computation. Quantum mechanics is constantly injecting fresh, random bits into the universe. Because of its computational nature, the universe processes and interprets those bits, naturally giving rise to all sorts of complex order and structure.
Aristotle, when he had finished writing his Physics, wrote his Metaphysics: literally „the book after physics“. This chapter has discussed the physics of the computing universe and its implications for the origin of complexity and order. Let us use the physics of the computing universe as a basis for its metaphysics.

105 Henry Stapp Minds and values in the quantum universe