Here are some of the things I have worked on recently:

I spent most of 1999 visiting the Supernova Cosmology Project at Lawrence Berkeley Lab, working on one of the most exciting scientific projects around. The tentative conclusion from this project, and from the work of a competing group, the High-Z Supernova Search, is that not only is the universe expanding, as has been known for over 70 years, but its expansion is accelerating. There is a way to accomodate this acceleration in cosmological models; it is attributed to vacuum energy, or what in this context is called the "cosmological constant". Trying to explain why the energy density of the vacuum has the value that it now appears to be have a challenge to theoretical physicists.

 

---

The Sciencenter is a hands-on science museum where I have designed and built many exhibits over the past several years.

---

Here is a site with lots about polyhedrons and many links to related sites: George Hart's site.

The Many Faces of Polyhedrons. This is program that I wrote which allows you to interactively manipulate virtual regular polyhedrons (cube, dodecahedron …) and semiregular polyhedrons (e.g. the truncated icosahedron – the soccer ball shape), as well as a few others. You can transform them into each other in various ways, rotate them, and display them in different ways. Go to my The Many Faces of Polyhedrons page for more information and to download it.

---

Imagine an “ant” on a square of a chessboard. It moves to neighboring square and turns right, and then moves ahead to the next square and turns right again. Imagine that it keeps doing this, but that when it comes to a square that it has visited once before, it turns left instead of right. And the next time it visits that square it goes right again, etc. What will happen?

See Prof. Scott Sutherland's web page about ants.

 

I have written some ant programs which implement some generalizations of the ant described above - ants on a hexagonal lattice ("bees"), ants in 3 dimensions, etc. Four programs (for Windows) together with some potentially helpful text are zipped into one file, "ants.zip". Download ants.zip.