Before I started at The Game Assembly I studied and graduated from KTH with a bachelor's degree in engineering physics. My thesis was about elementary differential geometry in two dimensions, studying curvature for 2D surfaces embedded in 3D space.
The main aim of the thesis was to gain enough understanding about differential geometry to be able to state and prove a theorem about curvature of surfaces. The theorem stated that any compact, connected surface with constant Gaussian curvature is a sphere.
You can read the entire thesis here.