# Deep math of the folded pizza slice

**doctorow**#1

**d_r**#5

A few years back two of my colleagues won an award for a paper calculating the shape of the largest taco you could make from a given round tortilla:

http://www.maa.org/programs/maa-awards/writing-awards/the-worlds-biggest-taco

**vrplumber**#6

Nothing inspires violent confrontation like math and pizza.

Case in point: Teenage Mutant Ninja Turtles

**stefanjones**#8

Foods like pizza go WAY back. The Romans had something like it, served at stands on the street. The way that folks wandering the streets 2000 years ago ate oiled, spicy flat bread was almost certainly closer to the way busy New Yorkers fold and nibble than this fancy fork and knife thing.

**7lions**#10

Full disclosure - I didnāt read the linked article, butā¦

This seems to have been chased a bit too far down the rabbit hole. For Gaussian curvature to apply fully, Iām pretty sure the pizza slice would have to be totally inelastic - incapable of being at all stretched. This isnāt the case, so the pizza does flex ever so slightly.

A more useful way to put this would be that folding the pizza increases itās area moment of inertia, thereby increasing itās longitudinal stiffness and decreasing all local stresses to below yield values. Thatās probably somehow related to Gaussian curvature, but I havenāt thought through just how yet.

**wldmr**#12

mathematical principal

*sigh* I think the word is āprincipleā. ~~And you call yourself a writer~~ Just a heads up.

**Tribune**#13

and lo, as the great age approached the leadership of the houses of learning were turned over to the equations.

**Fluorescent**#14

only here you can find such a stupid article! proud to be an italian pizza eater (without math but with mouth)

**wldmr**#15

@mtdna donāt attack the person, attack the argument. @7lions is not wrong (at least in the first paragraph; Iām not qualified enough to comment on the second). The article does implicitly assume that the pizza doesnāt stretch, which seems dubious, given that it is of soft doughy construction.

More generally, Gaussian curvature is about idealized surfaces, and it isnāt obvious that its results should apply without qualifications to real life objects ā which, unlike idealized surfaces have a thickness, internal structure and, as we know, a fucking mind of their own.

**PhasmaFelis**#17

Not sure what you meanāthe article was quite enlightening, at least once they get past pizza into actual physics. Your hostility may say more about you than about the article.

**PhasmaFelis**#19

Huh, that is actually pizza-ish. Interesting. Iāve occasionally seen claims that the Romans invented hamburgers, also sold at street stands, but the recipe provided as documentation turns out out to be a sort of large meatball made with wine, bread crumbs, and spices. It sounds tasty, but Iām not sure where anyone gets āhamburgerā out of it.

**mtdna**#20

The article doesnāt implicitly assume it. It assumes explicitly - literally in bold face - that you donāt āā¦**stretch, shrink, or tear [the Gaussian curvature]**ā. Maybe you should join 7lions in the RTFA club.