High energy particle collisions in the vicinity of naked singularity

Abstract

In this paper, we investigate particle acceleration and high-energy collisions in the Joshi–Malafarina–Narayan (JMN-1) naked singularity spacetime, which, in the absence of an event horizon, allows infalling particles to turn back under specific angular momentum conditions. These outgoing particles can then collide with infalling particles, enabling the JMN-1 singularity spacetime to act as a natural high-energy particle accelerator. We derive the necessary expressions to compute the center-of-mass energy of two colliding particles and find that this energy can reach extremely high values, potentially even approaching Planck energy scales. If horizonless compact objects exist in nature, these high-energy collisions could substantially influence the surrounding physical processes and might give rise to distinct observational signatures. We also discuss whether phenomena such as a photosphere or shock waves could develop within the shadow region of the JMN-1 naked singularity as a result of high-energy particle collisions near the singularity.