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Updated: May 14, 2026

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Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding
Published on: September 23, 2018
The most efficient origami torus.
1Department of Mathematics, Brown University, Providence, RI 02902.
Summary
Researchers proved that origami tori cannot have 7 vertices but can have 8 vertices. This finding resolves questions about the most efficient vertex count for constructing these unique geometric shapes.
Area of Science:
- Mathematics
- Computational Geometry
- Topology
Background:
- Origami tori are three-dimensional shapes constructed from triangles meeting at vertices.
- The sum of angles around each vertex in an origami torus must equal 2π.
- Previous research explored the existence and properties of origami tori with varying vertex counts.
Purpose of the Study:
- To determine the existence of origami tori with specific numbers of vertices.
- To settle the question of the most vertex-efficient origami torus construction.
Main Methods:
- Utilized geometric and topological principles to analyze origami torus structures.
- Investigated the constraints imposed by angle sums at vertices.
- Employed proof-based methods to establish existence and non-existence results.
Main Results:
- Demonstrated that an origami torus cannot be constructed with exactly 7 vertices.
- Proved the existence of an origami torus with 8 vertices.
- Established a boundary for the minimum number of vertices required for origami torus construction.
Conclusions:
- The non-existence of a 7-vertex origami torus and the existence of an 8-vertex one are confirmed.
- These results provide definitive answers regarding the most efficient origami torus construction in terms of vertex count.
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