Dynamic constraints on Feynman's path integral

Bung-Ning Teng

Published Jan 1, 1968• 0 citations

Abstract

The Feynman's path integral in space-time is closely related, via classical Lagrangian theory, to Dirac's formulation of quantum mechanics.The essential point of this approach is in making use of the Lagrangian function in space-time and Hamilton's first action principle to construct the probability amplitude in conventional quantum mechanics.This formulation has, as mentioned by Feynman, mathematical and physical incompleteness.We have investigated a part of the physical incompleteness, which can be treated by using the classical technique of eliminating ignorable.coordinates.The corresponding conjugate momenta will then provide constraint relations, which can be used to reduce the Lagrangian function and the path integral to a modified form.The paths are now restricted, via the constraint relations, to limited configuration spaces.A general modified formulation is constructed for paths in a limited space-time region.An important special case is demonstrated.In the special case, Jacobi's action principle is employed to replace Hamilton's action principle, therefore, the paths thus formulated are in space-energy rather than in space-time.

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