报告摘要: More than 3000 exoplanets (planets outside the Solar system) have been discovered in the last two decades, including some Earth-like planets that could harbor water and life. However,many exoplanetary systems are "extreme" and quite unlike our own Solar System: hot Jupiters, super-Earths, compact muli-planet systems, circumbinary planets, etc. These extreme planetarysystems are changing our view of planetary formation. They raise many puzzles and require new theoretical ideas and tools for their proper understanding. 报告人简介:Dong Lai is Professor of Astrophysics at Cornell University. He received his undergraduate degree from the University of Science and Technology of China in 1988. He studied theoreticalphysics at Cornell University, receiving Ph.D. in 1994. He was the Richard C. Tolman Prize Fellow in at Caltech, and joined the Cornell Astronomy faculty in 1997. He has received the AlfredP. Sloan Foundation Fellowship and the Simons Fellowship, and also the Outstanding Oversea Young Scientist Award from National Science Foundation of China. He has held senior visitingpositions at Institute for Advanced Study, Harvard University, Kavli Institute for Theoretical Physics, Canadian Institute for Theoretical Astrophysics, and several research instiutes in China.Dong Lai directs the theoretical astrophysics group at Cormell, focusing on compact objects (black holes and neutron stars), exoplanets and planet formation.