Global Kerr uniqueness without analyticity

partial Rigidity / Uniqueness

Statement

Prove that any smooth stationary asymptotically flat vacuum black-hole exterior satisfying natural nondegeneracy assumptions is Kerr, without analyticity assumptions.

Mathematical prerequisites

Rigidity theory; Carleman unique continuation; stationary reduction; horizon geometry; elliptic-hyperbolic coupled systems.

Why it matters

This is the stationary counterpart to the dynamical Kerr stability problem.

Completion criteria

A complete answer must state a sharp hypothesis set and prove a global isometry to a Kerr exterior.

Implications if solved

Would finish the classical uniqueness story in the physically natural smooth category.

Last updated: 2026-04-05 · Edit on GitHub →