Paul Richards has taught at Columbia University since 1971, where he has conducted research on the theory of seismic wave propagation, the physics of earthquakes, the interior structure of the Earth, and the application of seismological methods to explosion and earthquake monitoring. He is a co-author of the advanced text “Quantitative Seismology” (available in Russian, Chinese, Japanese as well as English). He has been emeritus Professor of Natural Sciences since 2008, and is currently Special Research Scientist at Columbia. He served terms as a visiting scholar at the U.S. Arms Control and Disarmament Agency in 1984 and 1993, participated in CTBT negotiations, is a Fellow of the American Academy of Arts and Sciences, and received the Seismological Society of America’s 2009 medal for outstanding contributions in seismology. See http://www.ldeo.columbia.edu/~richards/PGRc.v.long.html for a list of publications.