The Bell Gedanken Experiment Model implements a simple 3D representation of Bell's adaptation of the Einstein-Podolsky-Rosen apparatus. A central source prepares a singlet state for two Spin 1/2 particles with a specified z-component. Each arm of the apparatus has Stern-Gerlach detectors that can be rotated about the y axis. The simulation  plots the data in a Up Up ?? pair number vs angle difference representation and compares the classical prediction to the quantum mechanical prediction for the expected value of  pairs.

The Bell Gedanken Experiment Model was developed using version 5 of the Easy Java/JavaScript Simulations (EjsS) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.   Double clicking the jar file will run the program if Java is installed.  You can modify this simulation if you have EjsS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Please note that this resource requires at least version 1.7 of Java (JRE).