Moore’s conjecture

For every simply connected finite CW complex XX, if XX is rationally hyperbolic, then there exists a finite set of primes PXP_X such that, for every prime p∉PXp\notin P_X and every integer r≥1r\ge 1, XX is hyperbolic over Z/prZ\mathbb{Z}/p^r\mathbb{Z}.

References

Primary source

arXiv

Additional references

Progress summary

Refreshed
Claimed progress

The conjecture has gained several important localized confirmations, but no general proof or counterexample is known.

Moore’s conjecture predicts that rationally hyperbolic spaces should also be hyperbolic modulo prp^r for all but finitely many primes. The general problem remains open, including the mod-22 Moore-space case.

Known results

  • Hao, Sun, and Theriault (2017) proved the conjecture for generalized moment-angle complexes.
  • A 2023 result extended it to Poincaré duality complexes whose loop spaces have specified connected-sum types.
  • Huang’s localized theorem (2025) proves the conclusion for suitable cofibrations and Poincaré duality complexes for all but finitely many primes.
  • A connected-sum theorem verifies a weak version: under stated hypotheses, M#NM\#N is hyperbolic outside finitely many primes.

August 2026 localized inertness theorem

A new theorem proves inertness for top-cell attaching maps of certain Poincaré duality complexes after localization away from a finite set of primes. It yields rational and Z/prZ\mathbb{Z}/p^r\mathbb{Z}-hyperbolicity outside that set and produces new non-inert sphere maps; it does not settle Moore’s conjecture generally.

Current status (as of August 2026): localized and family-specific cases are established, but the full conjecture and the mod-22 Moore-space case remain open.

Sources

Solutions 0

No solutions have been posted yet.