David W. Ball

In Parts I-III of this series, columnist David W. Ball recounted the failings of classical mechanics, the quantum hypothesis, and the rise of a new theory called quantum mechanics. In this installment, he discusses the ideal systems whose wavefunctions can be determined exactly from the Schr?dinger equation.

Columnist David W. Ball discusses the pioneering work of Erwin Schrodinger, whose work on wave mechanics forms the basis of the modern understanding of subatomic behavior.

In part I of this series, columnist David Ball laid the groundwork for why the scientific understanding of nature in the late 19th century was found wanting: it could not explain a variety of phenomena that scientists were examining. (One of these phenomena was spectroscopy itself!) In this installment, he reviews the paradigm shifts in science that preceded the development of the currently accepted theories of the nature of matter. It all starts with the nature of light.

In this first part of a multipart series, columnist David Ball reviews the failures of classical mechanics that necessitated the development of a new theory of nature.

September 2006. An unusual form of spectroscopy uses light and sound to probe the behavior of materials. Here is a brief introduction to photoacoustic spectroscopy.

Some types of spectroscopy work better if the intensity of the light source increases and decreases in a regular pattern. Such a varying signal is called modulated, and here, the author explores the devices that perform this function.

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