Singularity theorems for the Reissner-Nordstrom spacetime and topology change in regular black holes

In this work we show several singularity theorems which can be applied to the Reissner-Nordstrom spacetime. To date, only two results [Phys. Rev. D 50, 3692 (1994); Lett. Math. Phys. 110, 2383 (2020)] have predicted null incompleteness in this case. In addition, we show that regular black holes in the Bardeen category have noncompact slices without the standard assumption regarding the knowledge of regions at infinity and, therefore, that they exhibit topology changes.

Automated summary

In this work, several singularity theorems applicable to the Reissner-Nordstrom spacetime are presented. Only two previous studies have predicted null incompleteness in this scenario. Additionally, it is shown that regular black holes in the Bardeen category have noncompact slices and may exhibit topology changes without the standard assumption about infinity regions.