Introduction to Crystals and Lasers - Symmetry and Physical Characteristics of Minerals and Gemstones - Lecture 1

Explore the fascinating world of crystals through this 57-minute Christmas lecture that examines the symmetry and striking physical characteristics of minerals and gemstones. Discover how the optical, thermal, and electrical properties of colored solids reveal crucial information about crystal interiors and the nature of light itself. Learn about the processes behind color creation, light emission, and the fundamental differences between incandescence and laser action through demonstrations of both natural minerals formed over geological time and laboratory-created crystals. Investigate how ultraviolet light and electron illumination induce luminescence in various materials, providing insights into crystal structure and behavior. Understand the historical significance of crystals that appeared millions of years before life emerged on Earth, contrasted with the relatively recent development of the first ruby laser less than thirty years prior to this 1987 presentation. Gain appreciation for the crucial roles crystals and lasers play in modern applications including materials design, communications, medicine, environmental science, and clean energy research, while witnessing key historical experiments that shaped our understanding of physical sciences.