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arXiv:2103.13727math.MG

Conway's spiral and a discrete Gömböc with 21 point masses

Gábor Domokos, Flórián Kovács

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Abstract

We show an explicit construction in 3 dimensions for a convex, mono-monostatic polyhedron (i.e., having exactly one stable and one unstable equilibrium) with 21 vertices and 21 faces. This polyhedron is a 0-skeleton, with equal masses located at each vertex. The above construction serves as an upper bound for the minimal number of faces and vertices of mono-monostatic 0-skeletons and complements the recently provided lower bound of 8 vertices. This is the first known construction of a mono-monostatic polyhedral solid. We also show that a similar construction for homogeneous distribution of mass cannot result in a mono-monostatic solid.

arXiv comments
13 pages, 2 figures
Journal reference
DOI
Subjects
math.MGMetric Geometry math.COCombinatorics

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    • The keyword is "mono-monostatic", and the Gömböc is an example of a non-polyhedra one: https://en.wikipedia.org/wiki/G%C3%B6mb%C3%B6c Here's a 21 sided mono-monostatic polyhedra: https://arxiv.org/pdf/2103.13727v2

      cbsksView on HNParent context

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