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arXiv · 2312.01325

Non-central sections of the regular n-simplex

Hermann König
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Abstract

We show that the maximal non-central hyperplane sections of the regular n-simplex of side-length sqrt 2 at a fixed distance t to the centroid are those parallel to a face of the simplex, if $\sqrt{(n-2)/(3(n+1))} < t < \sqrt{(n-1)/(2(n+1))}$ and $n>4$. For $n=4$, the same is true in a slightly smaller range for t. This adds to a previous result for $\sqrt{(n-1)/(2(n+1))} < t < \sqrt{n/(n+1)}$. For $n=2,3$, we determine the maximal and the minimal sections for all distances t to the centroid.

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Hermann König. 2023-12-03. Non-central sections of the regular n-simplex. https://arxiv.org/abs/2312.01325

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