The underlying structure of this tan cut and folded paper model might be seen as two triangular pyramids with a common base, facing opposite directions. Around the apexes of both of these pyramids are ...

Surfaces that can be represented by equations of degree two – spheres, ellipsoids, paraboloids, hyperboloids, and cones – have long been discussed in courses on descriptive and solid geometry, ...

Noncommutative geometry offers a radical reformulation of traditional geometrical concepts by replacing the classical notion of a manifold with a noncommutative algebra of coordinates. This approach ...