Huang, Hsin-Yuan2011-06-242011-06-242011-05https://hdl.handle.net/11299/107964University of Minnesota Ph.D. dissertation. Major: Mathematics. Advisor: Richard Moeckel. 1 computer file (PDF); vi, 47 pages, appendix p. 42-43.The objective of this thesis is to study variational methods in the Newtonian N-body problem. Chapter 1 contains the introduction of Chapters 2 and 3. Chapter 2 is devoted to the variational proof of the Schubart-like orbits in the collinear four-body problem. In Chapter 3, we discuss the limiting configurations of the action-minimizing triple collision orbits in the planar three body problem.en-USN-body ProblemVariational MethodsMathematicsThesis or Dissertation