Topology is weird: The Ham Sandwich Theorem

Опубликовано: 05 Февраль 2025
на канале: Dr. Trefor Bazett
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Today we talk about my favourite math theorem: the Ham Sandwich theorem. Consider a sandwich with three components. Then the theorem claims there exists some plane in three dimensions, where if I slice along that plane then I cut all three components exactly in half. We will see repeated use of the Intermediate Value Theorem in the simpler cases (which we call the pancake theorem), and then the more powerful Borsuk-Ulam theorem to prove the main result.

0:00 The Ham Sandwich Theorem
0:56 One Pancake and the Intermediate Value Theorem
2:12 The two pancakes theorem
3:40 Borsuk-Ulam Theorem
6:07 Proving the Ham Sandwich Theorem
10:45 Higher dimensions
11:24 Brilliant.org/TreforBazett

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