Higher-order Godbersen conjectures

For every convex body K⊂RnK\subset\mathbb{R}^n and for the admissible higher-order indices, the higher-order mixed-volume inequalities proposed by Schneider should hold. These conjectures generalize the classical Godbersen inequality for mixed volumes of KK and −K-K, namely V(K[n−i],(−K)[i])≥vol⁡(K)V(K[n-i],(-K)[i])\geq \operatorname{vol}(K) for 0≤i≤n0\leq i\leq n, together with the corresponding conjectured characterization of equality. The supplied source does not state the definitions and exact formulas of the two higher-order conjectures, so they cannot be specified more precisely here.

References

Primary source

arXiv

Additional references

Progress summary

Refreshed
Claimed progress

Recent papers claim substantial partial results, including the inequality portion of the higher-order conjectures, but the general conjectures remain open.

The higher-order conjectures generalize Godbersen’s inequality to higher-order difference bodies and mixed volumes. They were proposed in a February 2025 paper; the general inequality and its equality cases are not both settled.

Known results

  • The stronger higher-order conjecture is proved for anti-blocking convex bodies (February 2025).
  • Weighted-average inequalities and a separate conjecture for n≤5n \leq 5 were proved for the original problem (December 2024).
  • A July 2026 paper claimed a proof of the original Godbersen inequality and stated that its method extends to the higher-order inequality, but deferred the higher-order equality classification.

September 2026 partial results

A September 8, 2026 report describes claimed low-dimensional cases, weighted inequalities, and higher-order join bounds. These constrain possible general proofs but do not settle the higher-order conjectures; the July extension and the new claims remain unverified.

Current status (as of September 2026): Partial results and an unverified claim covering the inequality portion are available, while the general conjectures and higher-order equality characterization remain open.

Sources

Solutions 0

No solutions have been posted yet.