You may never look at a pizza or an orange in the same way again. Watch as astronomer, author, and teacher Cliff Stoll explains the *Theorema Egregium* or the Remarkable Theorem in this Numberphile vid. More via Aatish Bhatia:

Cut an orange in half, eat the insides (yum), then place the dome-shaped peel on the ground and stomp on it. The peel will never flatten out into a circle. Instead, it’ll tear itself apart. That’s because a sphere and a flat surface have different Gaussian curvatures, so there’s no way to flatten a sphere without distorting or tearing it. Ever tried gift wrapping a basketball? Same problem. No matter how you bend a sheet of paper, it’ll always retain a trace of its original flatness, so you end up with a crinkled mess.

Read more about the Remarkable Theorem at *Wired*, watch more math videos, and learn more with Numberphile.