Abraham "Avi" Loeb (Hebrew: אברהם (אבי) לייב; born February 26, 1962 In Beit Hanan, Israel.) is an Israeli-American theoretical physicist who works on astrophysics and cosmology. Loeb is the Frank B. Baird Jr. Professor of Science at Harvard University, where since 2007 he has been Director of the Institute for Theory and Computation at the Center for Astrophysics. He chaired the Department of Astronomy from 2011–2020, and founded the Black Hole Initiative in 2016.
Loeb is a fellow of the American Academy of Arts and Sciences, the American Physical Society, and the International Academy of Astronautics. In 2015, he was appointed as the science theory director for the Breakthrough Initiatives of the Breakthrough Prize Foundation.
Loeb has published popular science books including Extraterrestrial: The First Sign of Intelligent Life Beyond Earth (2021) and Interstellar: The Search for Extraterrestrial Life and Our Future in the Stars (2023).
In 2018, he suggested that alien space craft may be in the Solar System, using ʻOumuamua as an example. In 2023, he claimed to have recovered material from an interstellar meteor that could be evidence of an alien starship, which some experts criticized as hasty and sensational.
