Getting a handle on manifolds

If you’ve never heard of a “manifold,” a good place to start is to think of it as a shape. For much of human history, the question of the earth’s shape was hotly debated. Many people weren’t convinced that the earth’s surface was a sphere until the 16th century, when we developed the technology to circumnavigate the globe. The fact that humans inhabited the earth for millions of years without knowing its shape encapsulates the fundamental idea of a surface: if you’re living on a surface, such as the earth’s, you may not know what shape you’re on. All you know is that when you look around, the ground around you looks like a plane. In this talk, we’ll elaborate on this idea to develop a definition for manifolds. Then we’ll learn about handlebodies, which we can use to construct manifolds. By the end of the talk, you’ll have the chance to make your own handlebody, which you can take home to ponder further or show off to your roommate.