Problems Exterior Stability K-665
K-665

Prove quantitative mode stability for Kerr-de Sitter in full subextremal range and feed into nonlinear stability.

Conditional Classical frontier Open in literature Mostly scoped Exterior Stability Pure math FV: low
Kerr–de Sitter de Sitter Vacuum Linearized gravity NonlinearLinearExterior

Summary

Prove quantitative mode stability for Kerr-de Sitter in full subextremal range and feed into nonlinear stability.

Why this matters

Closes conditional gaps in Lambda>0 stability.

Exact scope

Background / setting
de sitter general relativity context; see family and coupling tags for matter model.
Equation type
PDE level: spectral/normal-mode analysis on fixed Kerr–de Sitter (linearized sector) with nonlinear stability as the downstream target.
Linearity
both linearized and fully nonlinear aspects
Regularity
Smooth / Sobolev hypotheses must be stated precisely in any final theorem; this provisional entry does not fix minimal regularity.
Parameter regime
Kerr–de Sitter moduli in the subextremal black-hole sector; spectral bounds are stated on the **fixed** background family before any nonlinear bootstrap.
Asymptotics
de sitter
Gauge / formulation
Conditional results depend on explicit spectral/mode-stability or gauge hypotheses; see status_explanation when curated.

Status explanation

**Conditional (explicit hypothesis):** quantitative mode stability is a **spectral assumption** on the fixed Kerr–de Sitter background (quasinormal-mode/gap-type bounds in relevant sectors); feeding it into nonlinear stability requires an additional bridge theorem—this entry names that split rather than asserting an unconditional nonlinear closure.

Problem statement

Prove quantitative mode stability for Kerr-de Sitter in full subextremal range and feed into nonlinear stability.

What is already known

  • Nonlinear stability of vacuum Kerr is proved for sufficiently small $|a|/M$ (Klainerman–Szeftel).
    Regime: Nonlinear Einstein vacuum, asymptotically flat, small angular momentum per unit mass.
    Strongest unconditional nonlinear theorem toward the full subextremal conjecture.
  • Linearized Teukolsky/wave decay and mode stability on fixed subextremal Kerr are developed in depth (microlocal and physical-space methods).
    Regime: Linearized gravity and scalar waves on exact Kerr.
    Standard toolbox; not equivalent to nonlinear stability for all parameters.
  • Sharp Price-law exponents and nonlinear tail matching are understood in restricted settings (e.g. linearized models, Schwarzschild); sharp nonlinear Kerr curvature tails are not settled.
    Regime: Late-time asymptotics; mixed linear vs nonlinear literature.
    Locates what “sharp Price law” demands beyond integrated decay.

Progress summary: Context: Closes conditional gaps in Lambda>0 stability.

What remains open

Prove quantitative mode stability for Kerr-de Sitter in full subextremal range and feed into nonlinear stability.

Mathematical prerequisites

Match hypotheses to primary sources cited on this page; state minimal regularity, gauge class, and parameter windows in any claimed theorem.

Completion criteria

Prove a theorem or give a rigorous counterexample that matches the scoped statement under explicitly listed hypotheses.

Implications if solved

Impact depends on the solved formulation; sharpen once the statement is pinned to a literature-compatible theorem.

Formal verification suitability

FV: low

Global PDE or phenomenological target; lemma-level formalization may be possible after scoping.

See Formal verification for how this database uses these labels.

References

Related by shared tags

Heuristic matches on family, cluster, equation level, asymptotics, and relevance.

  • K-608 — Prove unconditional nonlinear stability of slowly rotating Kerr-de Sitter.
  • K-609 — Prove conditional nonlinear stability of Kerr-de Sitter in the full subextremal range under explicit mode-stability assumptions.
  • K-667 — Prove stability/instability of the Cauchy horizon for Kerr-de Sitter under linearized gravity with sharp norms.
  • K-108 — Strong cosmic censorship in rotating $\Lambda>0$ black-hole interiors (conditional on a spectral–interior bridge)
  • K-601 — Prove unconditional linear stability of Kerr (full subextremal range) in a fixed gauge, with full decay rates.
  • K-602 — Prove nonlinear stability of Kerr for the full subextremal range |a|<M.
  • K-606 — Prove Kerr-Newman linear stability for a wider parameter regime beyond weak charge/slow rotation.
  • K-607 — Prove nonlinear stability of Kerr-Newman in the asymptotically flat setting (full coupling).

Editorial / maintainer notes

Source manifest: N-065 (expansion_from_manifest.tsv). Numeric footnotes from the original table are not reproduced in this repository.


Last updated: 2026-04-06 · Last verified (editorial): 2026-04-06 (bulk-editorial-fixes) · Edit on GitHub →