Weak and Strong Cosmic Censorship Hypothesis
The weak and the strong cosmic censorship hypothesis are two conjectures concerned with the global geometry of spacetimes.
- The weak cosmic censorship hypothesis asserts there can be no singularity visible from future null infinity. In other words, singularities need to be hidden from an observer at infinity by the event horizon of a black hole.
Mathematically, the conjecture states that, for generic initial data, the maximal Cauchy development possesses a complete future null infinity.
- The strong cosmic censorship hypothesis asserts that, generically, general relativity is a deterministic theory, in the same sense that classical mechanics is a deterministic theory. In other words, the classical fate of all observers should be predictable from the initial data. Mathematically, the conjecture states that the maximal Cauchy development of generic compact or asymptotically flat initial data is locally inextendible as a regular Lorentzian manifold.
The two conjectures are mathematically independent, as there exist spacetimes for which the weak cosmic censorship is valid but the strong cosmic censorship is violated and, conversely, there exist spacetimes for which the weak cosmic censorship is violated but the strong cosmic censorship is valid.
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