NCKU Math colloquium
DATE	2008-04-17　16:10-17:00
PLACE	數學館地下室演講廳
SPEAKER	陳國璋教授（國立清華大學數學系）
TITLE	The three-body problem from a variational point of view
ABSTRACT	The three-body problem concerns the motion of three celestial bodies moving in space in accordance with Newton's law of universal gravitation. Except for self-similar solutions, which were completely classified by Euler and Lagrange in the 18th century, classical existence proofs for solutions of the three-body problem are largely relying on a perturbation method due to Poincare. A vast amount of solutions were discovered by numerical simulations but yet without any analytical proof for their existence. In recent years variational methods have been successfully applied to the n-body problem to construct miscellaneous solutions. In this talk I will briefly describe these recent progresses on the three-body problem. In particular, I will outline a variational proof for the existence of retrograde triple stars and some bizarre planets for double stars