02 The Union of Electricity and Magnetism

THE UNION OF ELECTRICITY AND MAGNETISM We now know that lightning is a form of electricity and that the objects that attract iron are magnets. We also know how the 2 phenomena of electricity and magnetism interact with one another. We have even invented a term that makes this connection obvious: electromagnetism. The development of the formal theory of unified electromagnetism took more than a century. To understand the enormous magnitude of this achievement, we need to immerse ourselves in the science of the 19 th century and learn about the details of both electricity and magnetism separately. Only then can we understand how these 2 seemingly different phenomena actually originate from the deeper unified theory that we now call electromagnetism.