The Ejs Free Particle Wavepacket model displays the time evolution of a free (V = 0 everywhere) initial Gaussian wave packet in position and momentum space.  The default wave functions have <x> = 0 and <p> = 0, respectively.  The initial width of the position-space wavepacket can be changed with the slider. You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item.  

Ejs Free Particle Wavepacket model was created using the Easy Java Simulations (Ejs) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_qm_FreeParticleWavepacket.jar file will run the program if Java is installed.  Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models.  Additional Open Source Physics programs for quantum mechanics are available.  They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Please note that this resource requires at least version 1.5 of Java.