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Introduction

Thematic Essay: Physics, from Leonardo to Hertz

Thematic Essays combine a broad survey of a particular topic with key supplementary readings to create a comprehensive learning experience. In this essay, Nobel Prize-winning physicist Leon Lederman traces the development of classical physics. Accompanying the essay are Sidebars consisting of excerpts from the works of some of the world’s most influential scientific thinkers.

By Leon M. Lederman

The great English physicist Sir Isaac Newton once remarked, “If I have seen further it is by standing on the shoulders of giants.” Indeed, much of what physicists know today can be traced to the giants who lived during a period of scientific discovery often referred to as “classical physics”—a period that runs roughly from the time of Leonardo da Vinci in the 15th century to the time of Heinrich Hertz in the late 19th century. During this nearly 400-year period, many of the key concepts in physics, such as the notion of inertia and the ideas of gravity, electricity, magnetism, and light, were formulated and explained in a few simple equations. Looking back on this period in history and reviewing its accomplishments enable us to understand not only the physics of today but also the modern world we live in.

The period before the beginning of the Renaissance in the 15th century is often referred to as Western Europe's Dark Ages. The principal intellectual accomplishment during the Dark Ages was the preservation of the writings of the ancient Greeks, many of whom made important contributions to the study of science. This preservation was aided by the Egyptians in Alexandria and by the Arabs, who had translated some of the Greek scientists and philosophers, particularly Aristotle and Plato. With the blessing of the Roman Catholic Church, friars translated the Arabic versions of Greek science into Latin, the language of all educated people in Western Europe.

Largely through the work of the friars, the church accepted the teachings of Aristotle, the greatest of ancient Greek scholars. Unfortunately, Aristotle’s writings on astronomy and physics were misguided, and the church blindly adopted these errors. This uncritical approach made things difficult for Italian astronomer Galileo Galilei and others who created modern physics. By opposing Aristotle, they were opposing the Catholic Church, which was then all-powerful in Europe.

The spirit of intellectual curiosity during the Renaissance era, however, prompted a renewed study of nature without preconceived ideas. One of the most important figures in the Renaissance was Italian artist and scientist Leonardo da Vinci.