The Cosmic Microwave Background (CMB) radiation measurements offer some of the most powerful constraints in cosmology for supporting the accelerated expansion of the universe (cosmic acceleration). Rather than fitting a model to the entire dataset, we fit a model to three parameters that represent specific features of the CMB. The simulation allows users to compare and fit theoretical models of cosmology with recent CMB data sets to confirm the accelerated expansion of the universe. This modeling allows the user to vary cosmological parameters within a particular class of dark energy cosmological models to fit a particular cosmological data set. The user can plot several theoretical curves with the data to compare different models. The values of these parameters, for a particular model, determine the physical description and evolution of the universe.

The EJS Fitting Cosmological Data CMB model was created using Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_FittingCosmologicalDataCMB.jar file will run the program if Java is installed. You can modify this simulation if you have EJS by right-clicking within the plot and selecting Open Ejs Model from the pop-up menu item.

Please note that this resource requires at least version 1.6 of Java.