Our Research, explained for the public

Historical Background

Human Curiosity about the simplest building blocks of nature dates back to Democritos in ancient Greece (400 BC). He first postulated the concept of an indivisible constituent object. Only in the twentieth century was it realized, by Ernest Rutherford, that the atom consists of a central core (the nucleus), where all the mass is concentrated, and electrons orbiting this core. In the same period, Ernest Lawrence, Robert Van de Graaff, and others, probed nuclei by bombarding them with beams of high speed, charged particles, which is the underlying concept of the well-known atom smashers or particle accelerators. These early experiments established the existence of protons and neutrons (the nucleons) inside the nucleus and, in the process, laid the foundation for experimental nuclear and particle physics.

Over the past six decades, the basic properties, such as the mass, charge, and spin, of protons and neutrons have been determined. Most of this information has been obtained from scattering experiments. Typically, these experiments involve the bombardment of a target with a beam of energetic particles (such as electrons) and the detection and identification of the scattered particles. The higher the energy of the beam, the deeper one probes into the heart of matter.

About 30 years ago, nucleons were found to be composite objects, consisting of even smaller particles called quarks. The model which describes the cutting edge of understanding of nature among physicists, is termed, rather obviously, the Standard Model. It rests on the postulate that there exists a basic set of truly elementary particles (quarks and particles like the electron) whose interactions are governed by only four basic forces in nature: the gravitational force, the electromagnetic force, the weak nuclear force and the strong nuclear force. The first two are manifested in our everyday world, while the last two act only inside the nucleus.

 However, much is still unknown, and the Standard Model is under constant scrutiny, as is normal in science. Many of its features have been verified, but equally many have not, or, at least, not accurately enough.

Big Science, Big Time!

The ever increasing demands on higher energies for beams and more precise study of the scattered particles, has rendered subatomic physics, as possibly the Biggest among the big, in science. A typical international accelerator facility ranges in cost from half a billion to several billion dollars to construct, and on the order of a hundred million a year to operate, mostly due to the electricity bills. These facilities provide underground, cavernous halls (larger than the Agridome in Regina) for the placement of enormously complex and massive detectors, some weighing over ten thousand tons. These consist of computers, miniature electronics, special plastics and liquids, hair-thin long wires, tons of concrete, iron and lead, and tens of thousands of cables (much to the chargrine of the graduate students who have to connect them). So, when one adds the cost of these detectors to the bill, the cheque becomes very large indeed!

The Betterment of Humankind

In these days of cutbacks and tight budgets, why do almost all industrialized countries spend such huge sums of money on subatomic physics research? The answer is that such cutting edge research delivers many fruits.

Beyond the satisfaction of innate human curiosity in wanting to understand the surrounding world, there lie wide-ranging benefits from basic research. The investigations of scientists produce new knowledge, which is disseminated to university students and eventually to the public, thus contributing to education. International collaborative efforts promote strong bi- or multi-lateral exchanges, in scientific, cultural and economic terms. By investing in research in the USA, for example, Canadian researchers have seen a profitable return from their U.S. counterparts. Moreover, let us not forget that, besides writers and artists, scientists have often been on the forefront of human rights activities, such as in the ex-Soviet Union and China. Finally, the number of applications in technology, medicine and other fields, stemming from basic research in physics, are too numerous to reproduce here, but some examples are worth mentioning: radar, laser, cryogenics, ultrasound, Magnetic Resonance Imaging, various cancer treatments, to your very own TV and CD player. A large number of these came from subatomic physics.