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Nuclear Physics: Basic Research Servicing Society

Curiosity is the driving force behind research. Basic research does not aim specifically to create new inventions; instead, its purpose is to expand knowledge. This, in turn, serves as the basis for applied science, which strives to solve practical problems relevant to society.

In the early stages of discovery, it can be difficult to appreciate how useful basic research may become. As the 2006 Physics Nobel Laureate, Dr. George Smoot, once said, “People cannot foresee the future well enough to predict what's going to develop from basic research. If we only did applied research, we would still be making better spears." Throughout history, one has seen numerous cases illustrating the vital role of basic research in the advancement of scientific knowledge and of humankind as a whole. This could be elaborated in just a few important examples.

The current understanding of genetics and heredity is largely derived from Gregor Mendel’s experiments with pea plants in the 1860’s, and on the fruit fly experiments of T.H. Morgan roughly half a century later. Michael Faraday’s experiments with magnets and coils of wires allowed him to discover the principle of magnetic induction in 1831, and eventually led to the creation of many modern electrical devices, including radios, alternators, and power generators. Likewise, Wilhelm Röntgen’s late 19th century experiments with electric discharges in vacuum tubes led to his discovery of X-rays and its many applications in modern medicine. Similarly, in 1947, William Shockley, John Bardeen and Walter Brattain’s studies of the surface states of germanium led to their invention of the transistor, which is considered by many to be one of the greatest inventions in modern history. Transistors now serve as the foundation of all modern electronics and communication systems, including such necessities as computers, cellular phones, digital appliances, and even the Internet.

Like many other forms of basic research, research in the area of nuclear physics has yielded considerable benefits to society. Nuclear physics studies the structure of matter, its properties and interactions at the sub-atomic level. There are many applications and related techniques derived from nuclear physics which serve to address many of the challenges faced by society today. Still, the influence of nuclear physics in daily life is often overlooked.

Up to slightly over hundred years ago, most people thought that the atom was the most fundamental unit of matter, and that it was therefore indivisible. In 1897, Sir Joseph John Thomson, experimenting with currents of electricity inside empty glass tubes, discovered that the cathode rays produced were in fact streams of particles much smaller than atoms. He found that the rays were made up of electrons: the very small, negatively charged particles that are indeed the fundamental parts of every atom. J. J. Thomson’s discovery of the electron led to the invention of the television and almost all modern electronic devices used today.

In 1931, Ernest Lawrence invented the cyclotron, which became a powerful particle accelerator. Its offshoots are the synchrocyclotron and the synchrotron. Already shortly after its invention, the cyclotron was used to produce a plethora of radioactive isotopes. Many of these isotopes have been used by scientists in a diverse range of disciplines, including chemistry and biology, archaeology and paleontology. Of the various applications of nuclear physics and radioactive isotopes, perhaps the most important are the advancements in the life sciences, in particular the use of radioactive isotopes for medical diagnostics. Another well-recognized example is medical imaging. Technologies used to survey the human body include nuclear magnetic resonance (NMR or as it is known today MRI), computer-assisted tomography (CAT), and positron emission tomography (PET). Additionally, nuclear physics research has been used to develop techniques for the treatment of disease, including gamma-ray and neutron radiation, proton and ion-beam therapy. Together, these tools aid in the diagnosis of various physiological conditions and can contribute to an improved quality of life for affected patients.

The global issues of greenhouse gas emissions, high demand for electricity, and the increasing price of fossil fuels present a challenge not only to policy makers but also to nuclear physics researchers. Climate change is being described as an immediate threat to the welfare of current and future generations. Consequently, nuclear energy is being considered as an alternative to traditional sources. Initiatives in nuclear safety have begun to address such critical issues as the disposal of nuclear waste, and have thus alleviated concerns over the viability of nuclear energy. Whichever strategy society ultimately adopts to solve the energy problem, research leading to fusion reactors and towards the transmutation of nuclear waste will be of importance for future technical developments.

As researchers continue to develop new and exciting applications, nuclear physics will inevitably become increasingly far-reaching and inter-disciplinary in nature. Foremost ranks nuclear-astrophysics to explain the development of the universe after its first instant, the so- called “big bang”, and the abundances of the chemical elements. Nuclear physics has also made important contributions to a variety of fields beyond those listed above, including geology and oceanography, astronomy and forensic studies, and materials science. Examples for the latter are the use of stable energetic ions from accelerators which serve as versatile tools for structural analyses as well as modifications of solids. The analytical methods include channeling, elastic recoil detection analysis (ERDA), particle induced X-ray emission (PIXE), Rutherford back scattering spectroscopy (RBS), and focused beam scanning transmission ion microscopy (STIM). Ion beam analysis methods have reached high spatial resolution studying ultra thin layers of thickness a few nano-meters or less. Significant advancements in nuclear technology have been made in recent years, and it appears that research in nuclear physics will continue to have profound effects on humankind in the future.

Today, intense competition in the business world forces industry to focus on applied research. The onus is therefore on government and universities to perform the basic research necessary for the advancement of science and the creation of the foundation on which applied research can build.