Cosmic censorship hypothesis

The presence of gravitational singularities is perhaps one of the most disturbing features of Einstein's general theory of relativity. These are regions of spacetime where the curvature and density of spacetime go to infinity. Infinities could be results of the fact that Einstein's theory of general relativity has yet to be harmonized with the quantum theory, which describes the other 3 fundamental interactions: electromagnetism and the strong and weak nuclear forces. 

The cosmic censorship hypothesis is a pair of ideas (Penrose, 69) that says that in the general theory of relativity, any singularity in spacetime must lie behind an event horizon. Whenever a body collapses so that it produces a singularity, a black hole will form so that the singularity will be hidden behind an event horizon. The singularity would thus be completely unobservable to someone outside of the black hole. Both the weak and the strong version of the hypothesis concerns solutions to the Einstein field equations. 

The difference between the strong and weak censorship hypotheses is in how they are concerned with the global geometry of spacetime. 

The strong cosmic censorship hypothesis was proposed by Roger Penrose in 1986. 

The weak cosmic censorship hypothesis was proposed in 1988 also by Penrose.  

Naked singularities are excluded as solutions of general relativity.