First Shape Found That Can't Pass Through Itself
6 months ago
- #convex-polyhedra
- #mathematics
- #geometry
- Prince Rupert of the Rhine won a bet in the late 1600s proving that a tunnel could be drilled through one cube large enough for another cube to pass through.
- Mathematicians have since explored which other shapes, known as convex polyhedra, have the 'Rupert property' allowing one copy to pass through another via a straight tunnel.
- For centuries, only the cube was known to have this property, but in 1968, Christoph Scriba proved the tetrahedron and octahedron also have it.
- Recent research has identified many convex polyhedra with the Rupert property, leading to the conjecture that all convex polyhedra might possess it.
- Jakob Steininger and Sergey Yurkevich have now discovered the 'Noperthedron,' a 90-vertex, 152-face shape that cannot pass through itself, disproving the conjecture.
- The proof involved theoretical advances and extensive computer calculations, analyzing shadows cast by the shape in different orientations.
- The Noperthedron's discovery relied on a mix of global and local theorems to rule out all possible orientations for a Rupert passage.
- This breakthrough opens new avenues for studying shapes without the Rupert property and challenges previous assumptions in discrete geometry.