Physics What exactly is physics? What discoverieshave physicists been able to make, and what new discoveries are physicists making today Why bother discovering physics What is the excitement of physics What is the use of physics? Four hundred years ago the term physicist would not have been understood. The study of science was then the study of natural philosophy - a single discipline concerned with the scientific investigation of all natural phenomena, and the subsequent formulation of 'laws of nature' capable of embracing these phenomena. But since those Renaissance days, the growth of scientific knowledge has been so great that natural philosophy has divided into numerous different disciplines - physics, chemistry, Earth sciences, zoology, botany, metallurgy, meteorology, oceanography ... and many others. Nevertheless, it is perhaps true to say that of all the natural sciences, physics remains closest to the original ideal of those early natural philosophers it is that branch of science still most directly concerned with studying 'natural' events and with adducing the fundamental laws of nature. To attempt to define physics in a couple of sentences, however, is all but impossible. The dictionary describes it as 'the study of matter, energy, and motion. And certainly physics is, in large part, about understanding the material world, and the interaction of one part of it with another. Yet clearly, physics is also what physicists do, and as such it reflects all the kinds of abstract qualities that accompany any field of human endeavour. Physics is a curious mixture of creative effort and lucky discovery, of painstaking ex-
93 perimentation and mathematical deduction, of accumulated knowledge and unifying ideas, of philosophical implications and practical applications. Strangely enough, physics is also about faith and aesthetics. Many new insights in physics have been prompted by a firm belief (one based on nothing more than gut feeling) that the 'true' explanation of some phenomenon cannot possibly be as complicated as it would at first sight appear. Most physicists would agree that one of the goals of physics is to attempt to 'explain the world' with the simplest possible array of ideas and equations. Many would go even further and argue that the mathematics we use in doing this should be not merely useful, but elegant also And perhaps it is because physics displays all these many different facets that it is a fascinating, even if at times difficult, subject to study. Besides economic applications, physics has had a general cultural impact on the development of modern thought, particularly cosmology. Graduates from all courses are well-trained physicists qualified for entry into a wide range of careers, including academic physics, industry, the Scientific Civil Service, teaching and scientific computing. In addition, employers in nonscientific fields recognise the value of a training in physics every year a substantial proportion of our graduates embark on careers in finance, management and commercial computing. "Physics," it has been said, "is whatever physicists are doing"