Principle of least action
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Author: Dr. Chris G. Gray, Department of Physics University of Guelph
on Amazon.Dr. Chris G. Gray accepted the invitation on 21 October 2008 (self-imposed deadline: 21 April 2009).
Principle of least action refers to the original principle(due to Maupertuis) and the modern transformed version(due to Hamilton).We will define both the Maupertuis action and Hamilton action,explain the Legendre transform relation between them,show how the action principles can be used to solve problems without using equations of motion,and show the relation with quantum variational principles.Particle mechanics(nonrelativistic and relativistic) and fields will be discussed.It will also be explained how the(always stationary) action is sometimes "least",sometimes a saddle point,but never a maximum,for true trajectories of a system.
| Suggested by: | Dr. Edwin F. Taylor, Massachusetts Institute of Technology |
| Invited by: | Dr. Riccardo Guida, Institut de Physique Théorique; CEA, IPhT; CNRS; Gif-sur-Yvette, France |
