Larry Donnie Gladney (born 1957) is an American experimental particle physicist and cosmologist. In 2019, he became Professor of Physics and the Phyllis A. Wallace Dean of Diversity and Faculty Development at Yale University. Previously he was the Edmund J. and Louise W. Kahn Professor for Faculty Excellence, and Associate Dean for Natural Sciences, at the University of Pennsylvania. His research has focused on issues relating to the origins of expansion of the universe following the Big Bang, and on fundamental connections between matter, energy, space, and time. The recipient of many fellowships and prizes, and a former visiting scholar at the Lawrence Berkeley National Laboratory, Gladney featured in a 2006 oral history conducted by HistoryMakers, a digital archive project preserved