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arXiv · 2609.12483

The affine Tverberg theorem revisited

Sergey Avvakumov·Roman Karasev
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Abstract

We prove the Bárány--Kalai--Tverberg conjecture extending the affine version of Tverberg's theorem to simplicial balls and polytopes other than the simplex: For any affine map $ϕ: P\to \mathbb R^d$ from a convex polytope $P$ of dimension $N=(d+1)(r-1)$ with $r\geq 2$, there exist $r$ pairwise disjoint faces $F_1,\ldots,F_r\subset\partial P$ such that $ϕ(F_1)\cap\dots\capϕ(F_r)\neq\varnothing$. A similar statement holds for a simplicial ball $P$ with $ϕ$ assumed affine on all of its faces.

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Sergey Avvakumov, Roman Karasev. 2026-09-11. The affine Tverberg theorem revisited. https://arxiv.org/abs/2609.12483

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