3D print for stereographic projection; printed per Professor Edward Burkard for teaching. More information at https://www.thingiverse.com/thing:202774
This model demonstrates the process of stereographic projection. Stereographic projection (https://www.thingiverse.com/thing:202774) is a way to show that a sphere with one point removed is equivalent to the plane (they’re diffeomorphic, in math vernacular). If you hold a light (like the light on your cellphone) where the north pole of this sphere would be, the shadow you see on the table will be the usual grid lines on the plane (it will look like the lines on a piece of graph paper)! If you hold the light just right, you will see a bunch of squares on the table! Since light travels in straight lines in all directions from its source, she shadows are mimicking the process of stereographic projection which (in this model) is performed by drawing a straight line from the north pole, though a point on the sphere, and seeing where it hits the plane (which is the table this model sits on). – by Prof. Edward Burkard