J. Daniel Kelley received a Ph.D. in Physical Chemistry from Georgetown University, and then joined Brookhaven National Laboratory, studying molecular collision theory. He next joined the McDonnell Douglas/Boeing Research Laboratory, working on projects ranging from analytical chemistry to laser development, and simultaneously served as an Adjunct Professor in the Chemistry and Physics Departments at the University of Missouri-St. Louis. After retirement as a Boeing Technical Fellow in 2001, Dr. Kelley spent two years as a Visiting Scholar in the Thermosciences Division at Stanford University, and has been a consultant to Boeing, NASA and the University of Minnesota. Jacob J. Leventhal received his Ph.D. in 1965 from the University of Florida, after which he became a Post-Doctoral Research Associate at Brookhaven National Laboratory. He joined the faculty at the University of Missouri – St. Louis in 1968 where he taught physics and conducted a research program in experimental atomic and molecular physics. He retired to Emeritus Status in 2015. During his career he published more than 100 research papers and is a co-author of Topics in Atomic Physics (Springer 2005) and Foundations of Quantum Physics (Springer 2008).