For almost twenty years, mathematicians Rick Mabry and Paul Deiermann have attempted to figure out the perfect way to slice a pizza for sharing. Turns out, mathematicians have been pondering pizza slicing problems since at least the 1960s. Mabry and Diermann have recently proved their pizza theorem and are now considering other related problems, like what happens if the pizza is square or, say, a 3D pizza, aka a calzone?