The formation of black holes in nonspherical collapse and cosmic censorship

Abstract

Circumstantial evidence favouring the broad conjecture that event horizons always form in gravitational collapse is summarized along with the mounting counterevidence to a more restrictive cosmic censorship principle, which would compel every singularity formed in the collapse to be enclosed within a horizon. A confinement theorem is presented, stating that a closed, initially-trapped 2-surface of fixed area that remains regular will act as a wall that permanently seals off its interior contents from causal influence on the environment.