My Favorite Porn - I

Watching math videos is a rarefied perversion, but a fascinating one none the less. The poster child is BottemasTheorem. The theorem is simple to state: Draw squares on AB and BC on two sides of the triangle ABC. Let R and S be the points on the squares opposite vertex B. Then the midpoint M of RS is independent of B.

The setup looks like this:
The point labeled M does not move regardless of how the red triangle is changed. Mathematica's Demonstration site shows the deformed triangle (below) but the understanding of the theorem conveyed by the triptych is nothing compared to the impression of the online demo.

Click on any of the images to go to the site and start the animation.

The mathematicians who stumble onto the Mathematica are mesmerized by the demos until the need to tap a kidney bring them back to reality.

If math doesn't attract you, you still might want to take a look. Measuring the Speed of Light with Marshmallows is fascinating even for mathphobes.

Enjoy.