Limits on the mass of compact objects in Hořava-Lifshitz gravity

It is known that there exist theoretical limits on the mass of compact objects in general relativity. One is the Buchdahl limit for an object with an arbitrary equation-of-state, which turns out to be the limit for an object with a uniform density. Another one is the causal limit that is stronger than the Buchdahl limit and is related to the speed of sound inside an object. Similar theoretical limits on the mass of compact objects in deformed Hořava-Lifshitz (HL) gravity are found in this paper. Interestingly, both the uniform density limit and the sound speed limit curves converge with the horizon curve at its minimum, where a black hole becomes extremal, i.e., M = q , considering the Kehagias-Sfetsos vacuum, which is an asymptotically flat solution in the HL gravity.