# Cosmic censorship conjecture in some matching spherical collapsing metrics

## TL;DR

This paper demonstrates that certain physically plausible spherical collapse models can produce globally naked singularities, challenging the cosmic censorship conjecture by showing photons can escape from the singularity to infinity.

## Contribution

It provides a new example of a collapse model where the central singularity is globally naked, violating the cosmic censorship conjecture under specific conditions.

## Key findings

- Central singularity is globally naked in some collapse models
- Photons can escape from the singularity to null infinity
- Violates the cosmic censorship conjecture in these cases

## Abstract

A physically plausible Lema{\^{\i}}tre-Tolman-Bondi collapse in the marginally bound case is considered. By "physically plausible" we mean that the corresponding metric is ${\cal C}^1$ matched at the collapsing star surface and further that its {\em intrinsic} energy is, as due, stationary and finite. It is proved for this Lema{\^{\i}}tre-Tolman-Bondi collapse, for some parameter values, that its intrinsic central singularity is globally naked, thus violating the cosmic censorship conjecture with, for each direction, one photon, or perhaps a pencil of photons, leaving the singularity and reaching the null infinity. Our result is discussed in relation to some other cases in the current literature on the subject in which some of the central singularities are globally naked too.