Physics & Astronomy Applets

I've written a small number of Java applications (sometimes applets that can be buried in a browsers, sometimes standalone applications) that I've used in classes over the years. A few of them are below.

These things require Java. If you try to run them as an applet in the browser, they require the Java plug-in; Google for it if you don't already have it in your browser. If you download them to run then, you'll need to have Java installed on your system; you may well have it already. If not, it's available for zero cost, and can be found at

Make sure you have at least Java version 1.6 (also known as Java 6) for everything below to work.

Spiral Galaxy Rotator
A very astute student who was in my first introductor astronomy class asked, when I told them about the rotation curve of Spiral Galaxies, "why don't the spiral arms wrap up"? I wrote this applet in an attempt to demonstrate to those who couldn't see it why this would seem to be an issue.

Wave Play
A toy for demonstrating wave interference. Set up sources of sin waves that propagate left and right, and watch them interfere!

1d-Schrödinger Solver
An application that uses the JSci libraries to solve the one-dimensional time-independent Schrödinger equation for a handful of built-in potentials.