Frozen peas and carrots are commonly available in grocery stores in the United States. The carrots are cut into cubes roughly 8 mm on a side, while the peas are roughly spherical with a diameter of about 6 mm. They are prepared together in water that is brought to a boil. The peas and carrots, which are initially mixed together, separate as the water is heated. By counting the number of border vs. non-border vegetables before and after boiling, the decrease of the number of vegetables on the border demonstrates separation rather than chance rearrangement with the highly significant value p < 0.00001. The demonstration is a kitchen physics example of pattern formation in nonequilibrium systems.

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