JEREMIAH P. OSTRIKER, a Fellow of the American Academy since 1975, is the Charles A. Young Professor Emeritus of Astrophysics at Prince ton University and Professor of Astronomy at Columbia University. His research interests concern dark matter and dark energy, galaxy formation, and quasars. His publications include Heart of Darkness: Unraveling the Mysteries of the Invisible Universe (with Simon Mitton, 2013) and the volumes Formation of Structure in the Universe (edited with Avishai Dekel, 1990) and Unsolved Problems in Astrophysics (edited with John Bahcall, 1997). He was the recipient of the U.S. National Medal of Science in 2000.
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