On the Nature of Science, and the Beginning of Things.

I have been reading with interest Stephen Hawking's book, 'A Brief History of Time'. I was surprised to see it was first published in 1988. It seems like only yesterday when everyone was reading it, except me. Now I have caught up, it seems oddly relevant.

     Is this because not much has happened since in the world of high-energy physics? He seems to think that a great breakthrough might be imminent, starring string theory. It hasn't happened, and doubters are growing. Some of Hawking's remarks suggest an ambivalence, as though he was never convinced.

    A pattern had been established in the quantum theory, where a new piece of exotic maths was developed, and immediately was the key to a great breakthrough in theoretical physics. Some may have wrongly concluded that this was an inevitability, and so string theory would unlock doors just like complex numbers and matrix algebra had done. It hasn't happened. And why should it? You have to be using the right piece of maths.

     Tragically, public understanding of science seems to be in decline, largely as a result of the mischievous efforts of a few noisy persons. The quantum theory, particularly the Uncertainty Principle, gave rise to a new, more accurate and more humble understanding of what science was. You can't measure anything about a fundamental particle without bashing it with another one, affecting its properties. The realisation that measurement was meaningless in the abstract, that it was impossible to separate the observer from the observed, made people think more clearly about what science was all about.

     Hawking neatly summarises the new understanding in the first chapter: “..a scientific theory...is just a model of the universe, or a restricted part of it, and a set of rules that relate quantities in the model to observations that we make. It exists only in our minds and does not have any other reality...it must make definite predictions about the results of future observations.”

     This gives a realistic and rather humble view of what science is. Yet later on he also states: “..our goal is nothing less than a complete description of the universe we live in.”

     Isn't there a tension between these two statements? The first one reflects a widely-held understanding (originally due to Karl Popper) of what we really do when we do science. The second may be more peculiar to cosmologists.

     What Hawking doesn't discuss, is what one may call the Hamlet Effect: “Vanity, vanity, all is vanity.” Yet this impacts what actually happens in science as much as in other walks of life, and deeply undermines the objective view expressed in my first quotation from Prof Hawking. People don't want approximate models of restricted applicability, they want to understand the fundamental workings of the universe, and the conflict between this desire and the true understanding runs throughout the book. The history of physics is replete with instances of people declaring it a finished subject, even before the atomic nucleus had been discovered! Why are they obsessed with announcing that they know everything? Ask Hamlet.

     The general public is rarely treated to a realistic view of science, rather it is presented in an absolutist fashion, with disputes and differences of emphasis suppressed. Hawking makes many references to the role of God in the text of his book, often of a tentative nature, but saying things like “this leaves little for God to do”. Yet were he to stick strictly to his definition of science, he should rather have remained silent on the subject of God altogether. How can you “make definite predictions about the results of future observations” concerning the creator of the whole universe? An entity which necessarily would have some kind of existence outside of space and time themselves? If God exists, his properties as a totality are inconceivable to the human mind, almost by definition. In order to critique a concept as a scientific theory, it needs to be well-defined, or else it lacks the qualities of a scientific theory, and hence falls outwith the ambit of science. It is the tragic vanity of some scientists that they do not want to see this, almost seeming unable to grasp the idea that many ideas are simply not a science, and that does not mean they are wrong or inferior. It is impossible to incorporate an idea into science unless it can be subjected to systematic and precise observation. Sneering at other people's unscientific notions is not a part of science, rather it is a manifestation of the Hamlet Effect. Science consists of constructing models and comparing the results of observations with them, and that is all. There is neither necessity nor possibility to incorporate everything into a scientific model.

     Hawking mentioned that a scientific model exists only in our minds. Psychology is beginning to grasp that the human mind has certain in-built patterns of thought, in much the same way that a computer operating system has a limited library of system calls, and all programs runnable on that computer are some combination of this vocabulary. Other analogous situations include the fact that all DNA is some combination of chains of four amino-acids; all written words are a combination of a limited alphabet. What if the true nature of reality cannot be adequately modelled by the limited set of routines available to the human mind? Science would perforce remain incomplete. Why should an evolutionary process comprised of chasing animals about and throwing things at them give rise to a mental process capable of understanding the fundamental laws of nature? If we can do so, isn't that a bit of a miracle?

     Will cosmologists ever really succeed in writing an accurate history of time? I am sceptical. I suspect there are fundamental limitations on what can be detected from within the Solar System. Recent improvements in space technology have revealed how tentative and fluid our knowledge is. The public has been bombarded with enthusiastic propaganda about 'dark matter', a new form of matter postulated by astronomers which gives off no detectable radiation, and does not interact with ordinary matter. A recent space-based telescope of unprecedented sensitivity revealed that huge numbers of dim stars exist that had previously not been suspected. A significant proportion of the “dark matter” was instantaneously transformed into “dim matter”. I won't be surprised if much of the rest of it progressively goes the same way. Yet surely there can be ordinary matter too dim for even the most sensitive detector? Astronomers estimates of this are based on the vaguest of theories.

     Similarly, as the Voyager space probe has reached the edge of the Solar System, it has produced surprises about the nature of the stuff that lies between the stars.

     Isn't there a degree of vanity, never mind over-optimism, in trying to take an inventory of the entire cosmos? Yet without this, cosmology is impractical. Observations of such things as the cosmic background microwave radiation will always be subjected to multi-layered theoretical interpretation. The link between theory and the directly observable is unusually tenuous in cosmology, especially as it is historical rather than contemporary in character. Its deep problems and tentative nature are rarely mentioned in popular accounts which claim that science has somehow done away with God.

     An analogy popular with physicists considers the case of a race of hyper-intelligent ants trapped on the inside of a football. Their science may well conclude that the cosmos is curved, finite and has existed only for a limited time. They may consider the possibility of something outside of it, but will have no way of imagining what it might be, never mind detecting it. Unless someone starts kicking the ball.