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This java applet is a quantum mechanics simulation that shows the behavior of a particle in a two dimensional rectangular square well ("particle in a box").

In the center of the applet, you will see a plot of the wave function. The brightness indicates the magnitude and the color indicates the phase. At the bottom of the screen is a set of phasors showing the magnitude and phase of some of the possible states.

You may select a single state by picking one of the phasors at the bottom and double-clicking on it. Or, you may click on the phasor and drag its value to modify the magnitude and phase. In this way, you can create a combination of states.

You may create a gaussian wave packet by clicking and dragging on the position graph.

Full Directions.

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