Worst-case unrestricted translative covering density

How large can unrestricted translative covering density be for a convex body in dimension n? Translates need not form one lattice. Rogers’ general upper bound has order n log n.

Why it matters and what counts as progress

Why it matters: A matching lower bound would determine the worst-case order and exclude a universal linear bound.

What counts as progress: Convex bodies with unrestricted density at least c n log n in every sufficiently large dimension, or an improved universal upper bound; lattice-only examples do not suffice.

How the problem developed

  1. 23 Sept 2026 · Reported lower bound [1]

    OpenAI Reported centrally symmetric convex bodies in every sufficiently large dimension whose unrestricted translative covering density is at least c n log n, matching the order of the classical upper bound.

AI contribution

Translative covering densities of order n log n

OpenAI

For every sufficiently large dimension n, an OpenAI manuscript constructs a centrally symmetric convex body whose unrestricted translative covering density exceeds c n log n for an absolute c>0. With Rogers’ O(n log n) upper bound, this fixes the worst-case unrestricted order and rules out a universal O(n) bound.

AI involvementAI-led
ImportanceMajor
Technical verificationReported
Human understandingFew
Reported

Sources

  1. OpenAI, Translative covering densities of order n log n
  2. Translative covering densities of order n log n
  3. OpenAI, translative covering lower-bound theorem and context
  4. OpenAI, translative covering lower-bound conclusion
  5. OpenAI, translative covering lower-bound manuscript
  6. OpenAI, Lean theorem for translative coverings
  7. OpenAI, covering-density comparison statement
  8. OpenAI Math, release and provenance account
Website timeline

Publication dates and editorial changes.