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Unit 7: Manipulating Light

Unit Overview

This unit continues to develop the theme of the practical and foundational effects of quantum mechanics. It focuses on the experimental achievements in reducing the speed of light by factors of tens of millions and covers some of the implications of that research. The first section emphasizes the critical role that the speed of light in a vacuum plays in our understanding of our universe. It also outlines the "natural" way of slowing light by small amounts by passing it through materials of different refractive indices. Section 3 then details the type of experimental setup used to slow down light "artificially" in the laboratory and analyzes the fundamental quantum processes that permit physicists to reduce light's speed to that of a cyclist—and even to stop light altogether and hold it in storage. Next, Section 7 covers methods of converting light into matter and back again. And finally, Section 8 points out various applications, real and potential, of the increasing ability to manipulate light.