Garamvölgyi–Jordán–Király–Villányi rigidity-packing conjectures

For all positive integers dd and tt, every td(d+1)t d(d+1)-connected graph contains tt pairwise edge-disjoint spanning subgraphs, each of which is dd-rigid. More generally, for all positive integers dd and rr, every (d(d+1)+2r)\bigl(d(d+1)+2r\bigr)-connected graph contains a spanning dd-rigid subgraph and rr pairwise edge-disjoint spanning trees, all mutually edge-disjoint.

References

Primary source

arXiv

Progress summary

Refreshed
Claimed solved

A September 2026 paper claims to settle the two packing conjectures sharply, while the related orientation conjecture remains open.

The conjectures, posed by Garamvölgyi, Jordán, Király and Villányi, ask for sharp connectivity conditions guaranteeing edge-disjoint rigid spanning subgraphs, including a rigid subgraph plus a spanning tree. The associated orientation bounds concern Thomassen’s conjecture.

Known results

  • Villányi (2023): every d(d+1)d(d+1)-connected graph is rigid and globally rigid in Rd\mathbb{R}^d; the coefficient is sharp.
  • Villányi (2023): such graphs are (d+12)+1\binom{d+1}{2}+1-redundantly rigid and (d+12)\binom{d+1}{2}-redundantly globally rigid.
  • Earlier work gave only 10td(d+1)10td(d+1)-connectivity for tt disjoint dd-rigid spanning subgraphs and 320k2320k^2 for a kk-connected orientation.

September 21, 2026 claimed settlement

The cited paper claims that every K=∑idi(di+1)K=\sum_i d_i(d_i+1)-connected graph packs pairwise edge-disjoint spanning did_i-rigid subgraphs, sharply for K≥4K\ge 4, thereby settling both packing conjectures. It also claims f(q)≤(25q2+41q−16)/2f(q)\le (25q^2+41q-16)/2 and asymptotically f(q)≤(8+o(1))q2f(q)\le (8+o(1))q^2; f(q)=2qf(q)=2q remains open. These claims are unverified.

Current status (as of September 2026): The two rigidity-packing conjectures are claimed settled sharply but remain unverified, while Thomassen’s orientation conjecture remains open.

Sources

Solutions 0

No solutions have been posted yet.