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arXiv · 1204.3468

Rank-3 Projections of a 4-Cube

Steven R. Finch
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Abstract

The orthogonal projection of a 4-cube onto a uniform random 3-subspace in R^4 is a convex 3-polyhedron P with 14 vertices almost surely. Three numerical characteristics of P -- volume, surface area and mean width -- are studied. These quantities, along with the Euler characteristic, form a basis of the space of all additive continuous measures that are invariant under rigid motions in R^3. While computing statistics of {vl, ar, mw}, we encounter the generalized hypergeometric function, elliptic integrals and Catalan's constant. A new constant 7.1185587167... also arises and deserves further attention.

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Steven R. Finch. 2012-04-16. Rank-3 Projections of a 4-Cube. https://arxiv.org/abs/1204.3468

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