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Science shows how to evenly slice up a pizza (and you'll hate it)

Technically Incorrect: Two British mathematicians set about dividing up a pizza fairly. Some, though, will still feel hard done by.

Technically Incorrect offers a slightly twisted take on the tech that's taken over our lives.


Fairness isn't easy to achieve.

University of Liverpool screenshot by Chris Matyszczyk/CNET

Social justice isn't easy to achieve.

Somebody will always feel as if they have the short end of the straw. Or the smaller slice of the pizza.

This moved Joel Anthony Haddley and Stephen Worsley, mathematicians at the University of Liverpool in the UK, to wonder whether they could find the perfectly fair way to slice a margherita.

Their paper, eruditely entitled "Infinite Families Of Monohedral Disk Tilings" (PDF), seeks to find slices that are absolutely identical.

Pizzas are curved, rather than straight-edged. There's always a chance of desperate inequality, however hard you try.

But a monohedral disk tile -- a curved slice that has a very precise shape -- manages to create what these math-heads say is complete equality.

In order to achieve this nirvana of harmony, you first have to cut the pizza into six monohedral disk tiles. This might take the average human being around four years to perfect. This is my unscientific estimate.

After all, ensuring that each curvature is identical to every other isn't a task for most mortals.

Worse, you're still not done. You might need more slices. You could take the six you've already made and then slice them perfectly down the middle. (Another four years of practice, in my view.)

Once your confidence is high, you can keep on slicing until you have perfect mini-slices that will delight absolutely no one other than perhaps some ancient artist of nouvelle cuisine.


Do some now get the thin end of the crust?

University of Liverpool screenshot by Chris Matyszczyk/CNET

There's one slight drawback with this mini-slicing: some of the slices become predominantly crust.

The equality of size that's been so hard to achieve. It has, however, been sacrificed at the altar of ensuring that everyone gets a slice of something that actually resembles pizza.

There's something uplifting in the realization that math might not be able to solve everything -- in a real world sense.

These mathematicians have shown us that rational perfection is an achievable goal. But humans are dastardly.

Rationality doesn't satiate them. They need emotional satisfactions that are so hard to achieve. Even when they're achieved, they rarely last very long.

If we all had perfect slices of pizza, we'd soon find it dull. We'd want something new to fascinate us, something we could start to argue about.

How long would it be before humans wanted to find new, unequal ways of slicing pizza? Surely there'd be some who suddenly insisted they were monohedral disk tiling-intolerant.