What is Matter? This lecture reviews the nature of matter from

subatomic to atomic scales, and introduces the ideas of atomic

structure, atomic number (number of protons), the elements, isotopes,

radioactivity, and half-life. We conclude with a brief overview of the

four fundamental forces of nature: gravitation, electromatgnetic, and

the strong and weak nuclear forces. Recorded 2006 Oct 24 in 100

Stillman Hall on the Columbus campus of The Ohio State University.