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Efficient construction/description of low-surface-area tiling bodies

Ascertain whether there exist methods to efficiently describe or construct, for each n, a convex body K ⊂ ℝ^n whose integer translates tile ℝ^n, with vol_n(K)=1 and surface area vol_{n−1}(∂K)=n^{1/2+o(1)}, for example via a constant-factor polynomial-time optimization oracle or another comparably efficient representation, despite the fact that any such K cannot be represented as the intersection of n^{O(1)} half-spaces.

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Background

Recent work [NR23] constructs, for every n, a convex polytope K whose integer translates tile ℝn and whose surface area satisfies vol_{n−1}(∂K)=n{1/2+o(1)}. This is equivalent to an isoperimetric quotient iq(K)=n{1/2+o(1)} under the tiling condition vol_n(K)=1.

For potential algorithmic applications, an efficient description (e.g., polynomial-time optimization oracle) of such a tiling body would be needed. The paper’s Theorem 1 implies that the number of facets of any such K must grow faster than any power of n, ruling out a short half-space description as an efficient representation.

The authors therefore single out as open whether other routes to an efficient construction or description of such tiling bodies exist.

References

This rules out one possible approach to the aforementioned question, and it remains open to understand whether other routes towards obtaining an efficient version of a tiling body as in are possible.

Approximate isoperimetry for convex polytopes (2509.13898 - Ball et al., 17 Sep 2025) in Section “Historical comments”