By gluing together opposite pentagonal faces of a dodecahedron, we obtain a universe that satisfies the laws of spherical geometry. The number of spherical possibilities are infinite, but have been classified completely. Dr. Sarah's research relates to spherical universes. Build a dodecahedron in the back of the room. Notice that if you want to glue opposite faces together, we will need to do so with a twist, since the straight across gluing won't work. How many edges does the dodecahedron have? How many faces does it have? |