Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities

Abstract

We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularity representing spherically symmetric vacuum solution of the modified Hořava quantum gravity that is characterized by a dimensionless parameter $ωM^2$, combining the gravitational mass parameter $M$ of the spacetime with the Hořava parameter $ω$ reflecting the role of the quantum corrections. In dependence on the value of $ωM^2$, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures. In all of the K-S naked singularity spacetimes the tori are located above an "antigravity" sphere where matter can stay in stable equilibrium position, that is relevant for the stability of the orbiting fluid toroidal accretion structures.

44 pages, 27 figures multi panels