The Best Australian Science Writing 2012 (8 page)

Jim's quest for the ideal steam engine offers us a window into the science he would soon begin to articulate. In Jim's theory of the universe,
everything
is mechanical; like the INCOBO, the world he imagines is made up of simple interlocking parts. As with his engine, none of the parts is complicated and you don't need much mathematics to understand how it works. In this universe all matter and energy are explained by the mechanics of subatomic particles that are shaped like tiny circles of coiled spring. Jim calls this form the ‘circlon' and in his theory almost everything that happens in the physical world can be explained by the ways in which circlon-shaped particles interact. As in an engine, where gears intermesh, in Jim's universe all things happen through the intermeshing of circlon-shaped parts.

Diagram of a subatomic circlon by James Carter

Above all Jim believes that
atoms
are conglomerations of circlon-shaped particles. Here protons, electrons and mesons – the basic building blocks of matter – are simply different sizes of the basic circlon form and they link together to form a sort of subatomic mesh. Simple atoms such as hydrogen and helium are made up of just a few circlon-shaped particles, while more complicated atoms such as uranium are composed of several hundred. In this scheme, circlons fit together in a pattern that mirrors the structure of the Periodic Table – for Jim, Mendeleyev's iconic table is nothing less than a blueprint for a series of atomic-scale, circlonbased machines.

* * * * *

From the point of view of the physics mainstream, a mechanical universe is pretty hard to accept. To most academic physicists
circlons would seem as quirky as a steam-powered car. I say ‘would' seem because no university physicist has read Jim's book and to my knowledge I am the only person with a degree in physics who has. Jim's vision of the universe is quite literally old-fashioned, for until the middle of the 19th century most physicists
did
believe our universe was a machine. Descartes had famously proposed that idea in the early 17th century, and for the next 200 years mechanism was the scientific community's reigning natural philosophy. In the middle decades of the 19th century some of the finest minds in physics were actively trying to articulate mechanical explanations for such basic effects as electricity and magnetic forces. James Clerk Maxwell, the Newton of his age, spent decades trying to work out a mechanical explanation for the lines of magnetic force, which he tried to imagine as long thin hollow tubes snaking through space. For much of the history of modern Western science most scientific thinkers took it for granted that some kind of mechanical explanation would prevail for
all
natural phenomena.

But in the latter half of the 19th century a new paradigm worked its way into scientific consciousness and has dominated physics ever since. According to this way of seeing, our universe is not composed of any kind of concrete particles, but of something more ephemeral, what physicists call
fields
. The model here is the magnetic field, whose presence can be felt in the region around a magnet by its effect on iron filings. The invisible ‘field of influence' around a magnet gripped the imaginations of 19th century physicists and finally forced their thinking away from a mechanistic worldview. Maxwell himself was at the centre of this movement, along with Michael Faraday, and by the end of the century mechanism as a philosophy of nature had been relegated to the status of a historical curiosity. As the 20th century got underway most professional physicists had come to view the idea of the universe-as-machine on
a par with the
phlogiston
that was once thought to explain fire.

In the 19th century physicists had used field theory to explain electricity, magnetism and light. In the early decades of the 20th century that concept was extended to include matter itself, an extraordinary development that took even physicists by surprise. According to the new discipline of quantum field theory, a ‘particle' of matter is not a ‘solid' object at all, but an undulation or ripple in a quantum field that pervades our universe. Here the very concept of ‘object' is subverted and all our common-sense understandings of that word no longer hold true. ‘Objects' as we are used to thinking of them don't really exist in the universe of quantum fields. What we are offered instead is a kind of postobject worldview in which the very idea of hard, separate
things
is replaced by a mysterious web of influence. None of this is easy to come at, and as the great quantum pioneer Niels Bohr once remarked, ‘anyone who isn't confused by quantum theory hasn't understood it'. Most physicists initially found all this hard to accept themselves, yet quantum field theories are supported by equations whose experimental predictions have been borne out to dozens of decimal places. Field theories now underlie mainstream understanding of both matter and energy and are critical to the design of many contemporary technologies, including much of the telecommunication technology we have come to rely on, as well as microchips, a large class of which are made from ‘field-effect transistors'.

Practically speaking, we are all recipients of the revolution in thinking that the field idea has wrought, and anyone who uses a mobile phone or computer has reason to be grateful that physicists have come to understand this enigmatic aspect of our world. Psychically, however, we have paid a price, for the outcome of this intellectual upheaval is a description of our world that almost no one can understand. Fields have become, in effect, the black-box controls of our universe, the theoretical equivalents of the
microchip processors that control our cars. Just as the engine of the 21st century car has become a technological marvel that is inaccessible to backyard mechanics, so the 21st century universe has become an inaccessible wonder, a triumph of theory that can only be grasped by an expertly trained professional class. One way to think about what Jim Carter is doing is that he insists on a universe he can comprehend. As with the old Chryslers and Cadillacs that grace his front yard, Jim demands a cosmos he can figure out for himself.

* * * * *

Of all the things that human beings now do, theoretical physics is probably not one we tend to think of as accessible to a lone tinker's insight, not in the age of string theory and multi-billion-dollar particle accelerators. Since World War II theoretical physics has become a multinational industry wrapped around some of the most complicated facilities our species has ever constructed: the Hubble Space Telescope, the CERN accelerator, the LIGO gravity wave detector, the Ice-Cube neutrino detector at the South Pole, each of which bears a billion-dollar price-tag and each of which has huge technical crews devoted to its operation. These days, when research papers in experimental particle physics are published there are often several hundred scientists listed as authors, for that is the size of the teams it now takes to do many major physics experiments. Such vast collaborative enterprises have become essential for the progress of theoretical physics, which relies on experimental verification of its predictions to retain its credibility; without such machines, contemporary physics theory is in danger of becoming a mathematical game. It is a mark of the science's enormous success that indeed it now takes
so
much equipment and
so
many people to find something that is
not
already explained. The very abstraction of
current theory stands as a testimony to just how much physicists
do
understand, for it is only because they have explained so much that they find themselves now, on the fringes of the unknown, in truly bewildering territory.

Yet however exciting it may be to participate in such grandscale adventures, a yearning remains in some physicists' hearts for a smaller-scale, more personal kind of science. Dr Ken Libbrecht, a physicist I know at Caltech who heads one of the gravity-wave teams, retreats in his spare time from the stage of Big Science to a tiny laboratory where he builds machines to study how snowflakes form. It is something he can do on his own, he explains. On holiday from what he calls his ‘day job' with the LIGO team, snowflakes provide a frontier of research that he can explore by himself. In this field he is the unequivocal world leader, and, surprisingly, very little is known about the physics of ice crystallisation. Libbrecht once joked to me that with the papers he works on about gravity waves the list of authors may take up more pages than the article itself; simply keeping track of everyone's names is a significant challenge for a group leader. With snowflakes the headline is his alone and, what's more, he is following in the footsteps of scientific giants: Michael Faraday and Johannes Kepler, two of the most important physicists in history, both did research on snowflakes.

Ken Libbrecht isn't the only Caltech physicist who gets a kick from what we might call handmade science. The DIY impulse was also manifest in perhaps the most famous physicist in Caltech's history, the quantum theorist Richard Feynman. Feynman was the scientist who electrified the world on television with his demonstration of why the space shuttle
Challenger
blew up at its launch, killing all the astronauts on board. Those old enough to remember will recall how he dropped a rubber O-ring into a beaker of dry ice and water, causing the O-ring to shatter and thereby explaining how the spacecraft had failed. In 1965
Feynman was awarded the Nobel Prize in physics for his work on quantum field theory, yet in 1963 he had set out to perform a task that from the perspective of the scientific mainstream was the equivalent of building a steam engine.

The task Feynman set himself was to derive one of Newton's most important results without using any of the powerful mathematics now available to us. Specifically, he decided to reconstruct one of Newton's key proofs about gravity without using calculus, only using the laws of Euclidean geometry, a branch of mathematics that had been known to the ancient Greeks. Feynman wasn't doing this to advance the state of physics. He was doing it to experience the pleasure of building a law of the universe from scratch. Like Jim Carter with his steam car project, Feynman wanted to make something important using only the most rudimentary tools.

He presented the fruits of his labour to a class of undergraduates at Caltech as one of his legendary Feynman Lectures, and it was an achievement from which he had evidently gained an enormous amount of pride. Almost 300 years after Newton had presented
his
proof, Feynman set out to reprise the master's geometrical reasoning for his Caltech class. ‘I'm giving this lecture just for the fun of it,' he explained. Many of the students might already have done the proof for themselves with calculus – that is now an undergraduate exercise, and can be done with a single page of equations. Feynman himself noted that ‘it's much easier to do with calculus', and some of the students must have wondered why their professor was bothering them with this antediluvian version of the problem. Then Feynman described what he had in mind: ‘For your entertainment and interest,' he said, ‘I want you to ride in a buggy, for its elegance, instead of a fancy automobile.'

What Feynman set out to do was to prove that if Newton's law of gravity is correct then the planets
must
travel around the
sun in
elliptically
shaped orbits. Newton himself had shown that this was true and his proof played a pivotal role in helping to convince people of the 17th century that his gravitational law should be taken seriously. One must bear in mind that in the 17th century the idea of a mathematical law describing gravity was almost inconceivable. In that century, the very idea of an invisible force acting throughout space was itself heretical, for it seemed to smack of magic, and all that the new mechanistic science was trying to overthrow. Newton understood that his cosmology depended on the gravity law and that the fate of the new physics as a whole rested on his ability to convince his colleagues that what he was saying was real. In order to make them believe in his law he felt he had to demonstrate its truth using only the kind of mathematics they would completely trust. That meant he had to forego the new-fangled calculus he'd been inventing and use only the tried and true tools of geometry, tools that even the most conservative mathematicians would accept. Newton presented his gravity law, along with his geometrical proof about the planetary orbits, in the book that launched Newtonian science upon the world, the
Principia Mathematica
. Feynman wanted to understand exactly what he had done.

In the preparatory notes Feynman made for his lecture he wrote: ‘Simple things have simple demonstrations', then, tellingly, he crossed out the second ‘simple' and replaced it with ‘elementary'. For it turns out there is nothing simple about Newton's proof. Although it uses only rudimentary mathematical tools, it is a masterpiece of labyrinthine intricacy. So arcane is Newton's proof that Feynman could not understand it. That is because in the age of calculus, physicists no longer learn much Euclidean geometry; like stonemasonry, it has become something of a dying art. Feynman was rather surprised that he couldn't follow a piece of scientific reasoning now three centuries old, and he seems to have taken that as a personal challenge. Because he couldn't
understand Newton's proof he decided he had to do a version of it himself. The task nearly defeated him and the result of his work, when it was finally published, occupies close to 100 typewritten pages. It appears in a marvellous book called
Feynman's Lost Lecture
, by Caltech physicist David Goodstein and his wife Judith Goodstein, a former Caltech archivist.