Muhammed Amir

Rotating Hayward’s regular black hole as particle accelerator

A bstractRecently, Bañados, Silk and West (BSW) demonstrated that the extremal Kerr black hole can act as a particle accelerator with arbitrarily high center-of-mass energy (ECM) when the collision takes place near the horizon. The rotating Hayward’s regular black hole, apart from Mass (M) and angular momentum (a), has a new parameter g (g > 0 is a constant) that provides a deviation from the Kerr black hole. We demonstrate that for each g, with M = 1, there exist critical aE and rHE, which corresponds to a regular extremal black hole with degenerate horizons, and aE decreases whereas rHE increases with increase in g. While a < aE describe a regular non-extremal black hole with outer and inner horizons. We apply the BSW process to the rotating Hayward’s regular black hole, for different g, and demonstrate numerically that the ECM diverges in the vicinity of the horizon for the extremal cases thereby suggesting that a rotating regular black hole can also act as a particle accelerator and thus in turn provide a suitable framework for Plank-scale physics. For a non-extremal case, there always exist a finite upper bound for the ECM, which increases with the deviation parameter g.

Shapes of rotating nonsingular black hole shadows

It is believed that curvature singularities are a creation of general relativity and, hence, in the absence of a quantum gravity, models of nonsingular black holes have received significant attention. We study the shadow (apparent shape), an optical appearance because of its strong gravitational field, cast by a nonsingular black hole which is characterized by three parameters, i.e., mass (

Horizon structure of rotating Bardeen black hole and particle acceleration

M

Rotating Ayón-Beato-García black hole as a particle accelerator

), spin (

Collision of two general particles around a rotating regular Hayward’s black holes

a

Quintessence background for 5D Einstein–Gauss–Bonnet black holes

), and a deviation parameter (

Shadows of rotating five-dimensional charged EMCS black holes

k

Shadow of rotating regular black holes

). The nonsingular black hole under consideration is a generalization of the Kerr black hole that can be recognized asymptotically (

Shadows of rotating five-dimensional EMCS black holes

r\ensuremath{\gg}k,kg0

Shadow of charged wormholes in Einstein-Maxwell-dilaton theory

) explicitly as the Kerr-Newman black hole, and in the limit