5–9 Jul 2026
University of Canterbury
Pacific/Auckland timezone

Trapped Surface as a Cosmic Censor

6 Jul 2026, 12:25
2m
Room E8 (Rātā / Engineering Core Building, University of Canterbury)

Room E8

Rātā / Engineering Core Building, University of Canterbury

63 Creyke Road, Ilam, Christchurch 8041, New Zealand

Speaker

Daisuke Yoshida (Nagoya University)

Description

We formulate a local geometric criterion for weak cosmic censorship in black hole overcharging/overspinning thought experiments.
Matter satisfying the null energy condition generically focuses the null generators of the initial Killing horizon and turns a horizon cross section into a closed trapped surface.
Thus, any candidate final spacetime that cannot accommodate this surface is ruled out.
Applying this trapped surface criterion to Reissner-Nordstrom, Reissner-Nordstrom-de Sitter, and Kerr-Newman spacetimes, we exclude the corresponding superextremal final states.
This recovers the conclusions of the Sorce-Wald formalism without using asymptotically defined conserved charges, and provides a local geometric obstruction to the formation of naked singularities.
The charge-independent nature of the criterion opens the way to applications in spacetimes where asymptotic charges are absent or where no extremality condition characterizes naked singularities.

Research Area Mathematical and Numerical Relativity

Author

Daisuke Yoshida (Nagoya University)

Presentation materials