Science Literature

It is good advice to be wary of anyone purporting to represent the consensus in science. Those who speak the loudest about scientific consensus are often advancing other agendas. A good example can be derived from what people say about the 'scientific method'. Anyone practising science needs to know what it is, but in the real world, the progress of science often departs from the norm. Paul Dirac was a case in point. He was a theoretical physicist at Cambridge University who, in 1928, developed the maths that described the quantum behaviour of electrons. This led to the conclusion that it must be possible for an electron to have a positive charge. Later, Dirac described it as an "anti-electron" and when it was discovered in 1932 it was named the positron. The following year, Dirac received the Nobel Prize for his work. The first biography of this genius has been published recently and an informative review appears in the current Nature.

The unconventional Paul Dirac (Credit: Bettmann/Corbis, Source here)

Several characteristics of Dirac's work do not fit well with the consensus way of doing science. First, Dirac was a pure theoretician. He was not an experimentalist (although, later in life, this changed). He did not show any interest in stimulating a quest to find the positron.

"Although he commented that it could be made transiently in experiments, he was surprisingly circumspect, more concerned with the difficulties of detection than the inevitability of its existence. He made no suggestion as to how experimentalists might make it, or recognize it. He was away in the United States later that year when Robert Millikan gave a talk at the University of Cambridge, UK, showing Anderson's images of particle tracks from cosmic rays - including some that looked like those of electrons but which curved the wrong way in a magnetic field. No one associated these tracks with Dirac's holes."

Second, not brought out in the Nature review, but nicely described in other essays, Dirac was a theoretician who thought that elegant theory, beautiful maths and good science go together. Dirac was confident in his theoretical work, not because it had been confirmed empirically, but because it satisfied his aesthetic sense of the relationship between physics and the real world.

[Waldegrave]: "And yet Dirac's brand of theoretical physics, and the way he saw the world, was so close to philosophy. He was convinced that the more beautiful an equation, the more likely it was to be accurate - in other words, he saw a picture of the world that was of such beauty that it had to be true."
[and]
[Carey] "Even his fellow physicists complained that he worked in a deliberately mystifying private language. For his part, he insisted that the quantum world could not be expressed in words or imagined. To draw its picture would be "like a blind man sensing a snowflake. One touch and it's gone". Its beauty revealed itself only in mathematical formulae."

But the greatest contrast between the consensus scientific method and Dirac's research experience is found in the route to reach radical or revolutionary conclusions. Dirac was working on the frontiers of relativistic quantum theory and he was pioneering in his foresight of the "mirror world of antimatter". His colleagues were rather sceptical.

By 1932, the holes had become a joke. At a meeting in Copenhagen, when Bohr lost his patience and confronted Dirac with: "Do you believe all that stuff?", he simply replied, "I don't think anyone has put a conclusive argument against it."
[and]
[Waldegrave]: His great equation for the electron - an improbable marriage of relativity and quantum theory - only worked if you assumed that there was such a thing as an "anti-electron". His colleagues mocked the idea, but Dirac stuck to his guns: the maths was so harmonious that reality had to reflect it.

The hallmark of any revolutionary idea in science is that, before the transformation, the community of scientists are sceptical about the new ideas, with some expressing outright disagreement. After the change, the community applauds the new research - which becomes the new orthodoxy. The 'scientific method' knows nothing of this punctuated change, for it portrays an incremental step-by-step approach towards increasing knowledge. To explain scientific revolutions, we need something more. The analysis of Thomas Kuhn provides such an explanation, forcing us to think through the meaning of scientific paradigms. According to Kuhn, any community of researchers share a set of assumptions, concepts, values, and practices. This is their way of viewing the world and, generally, is exempt from being questioned or changed. Much can be done from within this conceptual framework, but observations will be found that create tensions or understanding. These tensions are the drivers for a paradigm shift, and the process of change can be traumatic.

Paul Dirac's pioneering work in quantum physics led to him sharing with Erwin Schrodinger the 1933 Nobel Prize for physics. This was awarded "for the discovery of new productive forms of atomic theory". He was Lucasian professor of mathematics at Cambridge from 1932 to 1969. His appreciation of beauty in the mathematics of the physical world is reminiscent of one of his predecessors in the Lucasian Chair. Isaac Newton had great confidence in the inverse square law of gravity. This confidence came because of his commitment to design in nature. Dirac is said to have been an atheist, but he is also reported to have said: "God used beautiful mathematics in creating the world".

These thoughts on the scientific method are being contributed because there are many strident voices insisting on what science is and what it is not. The claim that 'ID is not science' crops up repeatedly. Books and articles are published regularly making grandiose claims about the crisis facing science if students are even exposed to design-based thinking. What characterises them all is that they fail to engage with what ID scholars are actually saying. ID scientists are interested in truth. They operate within a different paradigm than scientists starting out with a materialistic philosophy. If there is a commitment to truth-seeking on all sides, then there has to be some way for scientists with different paradigms to interact meaningfully. Isaac Newton and Paul Dirac held the same professorial chair at Cambridge University - perhaps that provides a lesson for us all.

Paul Dirac: a physicist of few words
Frank Close
Nature 459, 326-327 (21 May 2009) | doi:10.1038/459326a

A detailed biography argues that the Nobel prizewinner's notorious reticence delayed experimentalists from discovering the antimatter that would confirm his elegant theory.