QGN stiffness conjecture

For every quantum geometric nesting (QGN) model with an exact frustration-free ground state and a spontaneously broken continuous symmetry, the exact stiffness associated with that symmetry equals the stiffness obtained by restricting the calculation to the Gaussian variational manifold: ρexact=ρGaussian\rho_{\mathrm{exact}}=\rho_{\mathrm{Gaussian}}.

References

Progress summary

Refreshed
Claimed solved

A recent unrefereed preprint claims to prove the conjecture for a special class of solvable quantum systems, but independent confirmation is absent.

The conjecture concerns exact formulas for stiffness and response functions in solvable QGN models. The reported result claims a complete resolution within that model class, not beyond it.

Known results

  • Foundational QGN work constructs solvable interacting flat-band systems and computes phase stiffness exactly in ideal cases (2024).
  • Numerical and bootstrap studies find close agreement with the conjectured stiffness formula, including exact agreement on a small system, but explicitly leave a rigorous proof open.

August 27, 2026 claimed proof

A linked preprint is reported to use Fock-space fragmentation to show that an infinitesimal phase twist couples the ground state only to the one-particle, one-hole sector, yielding exact stiffness and response functions for QGN models. This is a claimed solution and remains unverified; independently retrieved arXiv material instead describes bootstrap evidence and says a rigorous proof remains future work.

Current status (as of August 2026): A preprint claims a complete proof for QGN models, but the conjecture remains unverified and its scope beyond QGN models is unresolved.

Sources

Solutions 0

No solutions have been posted yet.