How to Cut a Hole in a Pumpkin That Is Bigger Than the Pumpkin

Our first problem comes from Eric V H via Twitter. What is the largest single hole relative to the size of the pumpkin? One can carve out of a pumpkin without the pumpkin collapsing. Can you cut a hole in a postcard big enough to climb through? Yes, you can because you cut it in such a way that a constantine is out and then you can fit.