Infinity Cube
Infinity Mirrors are cool decorative objects that look like they are the entrance into a seemingly infinite hallway. They are pretty simple to build, consisting mainly of a normal mirror, a two-way mirror, and a varying number of lights in between them (depending on how the maker wanted it to look). The reason it works is because the light from the bulbs on the inside bounces back and forth repeatedly between the two mirrors, while letting a little bit through each time it hits the 2 way mirror. This causes the viewer to see multiple duplicates of the lights on the inside, with each one being smaller and looking like it is farther back. Recently, I came across a photo of a cube someone built that used this same principle on every side. It wasn't just 6 infinity mirrors on each side, but 6 two way mirrors. This made it seem like you were looking into a fully 3d space extending beyond the interior of the cube on the other side. This intrigued me, and because finals were approaching, I didn't want to spend time building a physical model, so I made a simulation of it in a 3d program I use called Blender.
I was pretty happy with the result, and decided to show to it to one of my friends. After seeing it, he asked me what would happen if it was a sphere instead of a cube. We both couldn't figure it out in our heads, so when I got home from school, I made another simulation in Blender to see. To make it more interesting, I offset the light i put in the sphere away from the center.
This is an animation where the camera circles around the sphere continuously.
Each frame of each render took a good 5 minutes to render, and although the results looked cool, I wasn't quite sure why they looked like they did. Later, I built my own custom raytracing engine to see what a perfect infinity sphere would look like.