**Publication date:** Apr 2022

**Abstract:**

We study evolution of the braneworld Kerr-Newman (K-N) naked singularities, namely their mass M , spin a , and tidal charge b characterizing the role of the bulk space, due to matter in-falling from Keplerian accretion disk. We construct the evolution in two limiting cases applied to the tidal charge. In the first case we assume b =const during the evolution, in the second one we assume that the dimensionless tidal charge β ≡b /M^{2}=const . For positive values of the tidal charge the evolution is equivalent to the case of the standard K-N naked singularity under accretion of electrically neutral matter. We demonstrate that counterrotating accretion always converts a K-N naked singularity into an extreme K-N black hole and that the corotating accretion leads to a variety of outcomes. The conversion to an extreme K-N black hole is possible for naked singularity with dimensionless tidal charge β <0.25 , and β ∈(0.25 ,1 ) with sufficiently low spin. In other cases the accretion ends in a transcendental state. For 0.25 <β <1 this is a mining unstable K-N naked singularity enabling formally unlimited energy extraction from the naked singularity. In the case of β >1 , the corotating accretion creates unlimited torodial structure of mater orbiting the naked singularity. Both nonstandard outcomes of the corotating accretion imply a transcendence of such naked singularity due to nonlinear gravitational effects.

**Authors:**

Blaschke, Martin; Stuchlík, Zdeněk; Hensh, Sudipta;