Departments of
Physics and Astronomy
& Mathematics

4:00 PM, Thursday, February 16, 2006
Room 155, Chem-Phys Building

Dr. Eric Heller

Departments of Physics and Chemistry
Harvard University

``MAKING WAVES: a random walk through
the science, politics and art of wave physics''

The Greeks knew that sound traveled as a wave through the sea of air, but it was not until 1800 that the Wittenburg scientist Chladni discovered a way to see sound waves on vibrating glass and metal plates. This work became well known in Europe. Napoleon, a strong supporter of science, saw the demonstration and said ``Chladni has made tones visible'', which was a perfect way of putting it. His involvement went well beyond this, as I will relate in the talk. The Chladni plates were for many people a mystical connection between the senses and the vibratory world that lies beneath. This mysticism extended to some of the best scientists of the day, such as Oersted, the discoverer of electromagnetism, and the mysticism remains today. The impact of this work has a lot to do with the power of the image, and the notion that ``seeing is believing''.

While I am not quite so mystical about sound waves, there is no way to avoid the mystery of matter waves, which form the basis of quantum mechanics, an incredibly successful theory. Visualizing matter waves is a large component of what I and other scientists do these days. The talk will begin with Chladni, wind through W. Sabines pioneering work on acoustics, into the modern era of Eigler's electron wave quantum corral experiments, and Bob Westervelt's electron gas experiments (to be expanded in the Friday Physics and Astronomy Colloquium). A parallel theme involves the power of images to promote science, to be illustrated by many examples.