THE QUANTUM PENDULUM

The path integral formulation of quantum mechanics in the WKB approxim ation (quasi-classical) gives to us a useful tool to relate the classi cal systems (with or without chaos) with its quantum analogs. We use t his point of view to compute the eigenfunctions and energy eigenvalues for the quantum pendulum comparing with those obtained with the stand ard WKB approximation. The method that we employed in this work was de veloped mainly by Gutzwiller, and one of its main features is that thi s method can be used in integrable and no integrable problems.